Welcome to main Firenock lighted nock system FAQ page, where you'll find specification and feature questions not answered on individual product pages. Note that this page is separated into three sections for your convenience. Find details about each section as well as links to other Firenock FAQ pages below.
General FAQ: As the name implies, this section is the general or generic questions one might have about Firenock e.g. features, characteristics, use, maintenance, etc.
Battery FAQ: For any specific questions on Firenock batteries (and if you couldn't find your answer in troubleshooting [see below]), this is your section.
Extreme Shock End Cap FAQ: If you have any questions about the extreme shock end cap system (including ESEC troubleshooting concerns), this is the place.
On other pages...
FLNS Troubleshooting FAQ: Whenever something doesn't go as planned or hoped, this page offers possible solutions.
FLNS Modification FAQ: For those who have more...unusual arrows, we might have a Firenock modification option for you.
Aerovane FAQ: Check this page for some clarifications and hints on this complex product.
The Firenock lighted nock system is not just a simple wire with an LED attached or some custom integrated circuit glued into a stock nock. Firenock is different because it was designed differently. It was designed, with no expense spared, to be as reliable and consistent as possible–it was designed to last a lifetime. Loaded with multiple independently claimed patents, Firenock's uniqueness is found upon its PCB or printed circuit board. Including a G-switch, a motion sensor and digital timer, our lighted nock system's PCB will last for 30 thousand shots.
Let's get into each component on our double layered PCB.  The G-switch. See, the Firenock activates itself without a visual or physical switch. Instead, our G-switch, an acceleration switch, as the name implies, requires a minimum of 65 Gs of force (with a tolerance of three degrees). This precondition eliminates the chance for accidental activation or deactivation. The motion sensor and digital timer, sitting on the second layer of the PCB, on the VLSIC or very-large-scale integrated circuit, further assist in that. A closed system, the motion sensor and digital timer work together to ensure that only YOU can turn off (and on) your Firenock lighted nock system. See question GQ4 to learn exactly how.
Though spectacular alone, our PCB is accompanied by equally spectacular consumable accessories. For example, our nocks. Made with the best polycarbonate (Makrolon™ by Bayer®) and dye (Makrolon™ by Bayer®), every style of our nocks is guaranteed to be the same weight, no matter what color. The mold itself, in particular, took 160 hours of engineering and 10 molds to perfect. Now, a multiple piece mold is used to make each nock. Further, molded in its own cavity via virgin flow, every nock can and does have its own mold mark and cavity number for quality control. All this, to ensure the best light transmission and consistency.
Other essential Firenock components include our custom batteries and custom extreme shock end caps. Epoxy-sealed and chemically formulated, our batteries have an average shelf life of up to 13 months (when stored at room temperature) and can work from below freezing to above 100° F. See battery page for specifics. Our ESEC, on the other hand, are CNC machined and thus meant to last forever.
"The above mentioned may sound very scientific and technical, but without these details it is not possible to achieve perfection. Bringing you "The Most Advanced Lighted Nock" is not an easy thing and it's definitely not an inexpensive venture. Firenocks are simple to use and reliable because we put so much effort in them and that is how we ensure that the Firenock that you purchased will work as described." -Dorge Huang
For even more information on your Firenock lighted nock system style's specific features, check out our Firenock Selector.
Besides all the reasons we've listed above in GQ1, let's articulate some more specs about the G-switch (the most expensive component of the Firenock lighted nock system). Our G-switch is the smallest acceleration switch ever built commercially at only 2 mm in diameter and 6 mm in length. Due to being hermetically sealed and accompanied by 24k gold-plated components, our switch can handle no less than 12,000,000 cycles of activation and up to 15,000 Gs of force (from a perpendicular direction from the G-switch pin). ...Isn't it easy to understand why Firenock lighted nocks are more costly than other brands of nocks?
GQ3: What do the Firenock lighted nock system codes mean? See this page.
Follow these directions carefully.
- Wait at least 6-8 seconds after activation before trying to deactivate the system.
- Lift the arrow (nock end down) no less than 8 inches (20 cm) above a semi-hard flat surface*.
- Drop the arrow (still nock end down) onto the surface via gravitational force. Upon impact, the Firenock will deactivate automatically. If the lighted nock does not deactivate, repeat steps 2 & 3 and increase the distance by two inch (5 cm) increments until the unit deactivates.
*A pine block, the top of your boots, or the floor inside your truck are good examples of semi-hard flat surfaces. If the Firenock does not shut off after a free-fall distance that is as high as 12" (30 cm), please return your Firenock for warranty replacement.
The Firenock lighted nock system is available in three different light functions: Hunting (H), Target (T), and Intermittent (I). The Hunting (H) circuit, for standard or common sized arrows, will remain lit until the battery runs out or is manually switched off. This function is also available for slim arrows (N) and ultra-slim arrows (Z). The Target (T) circuit, for standard or common sized arrows, will turn off automatically after 17 seconds. This function is also available for slim arrows (K) and ultra-slim arrows (0). The Intermittent (I) circuit, for standard or common sized arrows, will remain lit for 6 seconds and will then blink until the battery runs out or is manually switched off.
The Firenock lighted nock system boasts complete interchangeability. There are currently up to 9 nock colors per style and up to 6 LED circuit colors per series of circuit, with thus a total of 54 color combinations. All styles of Firenock are immediately available in all 6 LED colors. The same cannot be said for nock colors. See replacement nock page and click each style to see what is currently available.
Firenock offers up to 54 colors of lighted nocks to suit almost all lighting conditions. In most cases, one cannot go wrong with a red nock on a red LED.
Many may think that a “clear” or white LED will give you the maximum amount of visible light. The reverse is true. Consider the lights on your car. When lit, a headlight has over 10,000,000 lux while a stoplight of a car (which is a red bulb covered by a red lens) has about 50,000 lux. A stoplight is on average at least 200 times less bright than a headlight, yet it is still as, if not more so, immediately identifiable. A white light will provide sight when you want to shine on something and look for its reflection, but it cannot compare to the effect of red light with a red lens when you are looking into the light. For a normal human eye, red on red is over 95% more effective under all such conditions. This is why all cars have a red bulb with a red lens as a stoplight.
But what about a clear nock? Wouldn’t it be the best over colored LEDs since it will allow the most light to pass through? Reusing our car light example, recall what a broken tail looks like. Due to the fact that there is no lens on the light source, a high starburst/halo effect occurs. This weakens instead of strengthens visibility.
For clarification’s sake, let us discuss some other color combinations. While color can also just come down to personal preference, some combinations have great particular advantages.
- Some may think that a green LED with a green nock is great for all conditions. It is important to note always that Firenock results in not color, but colored light. And while it might be debatably easy to see the color green (like from a sight pin), a green light cannot compete with the sun's direct opposing light. It bleeds out easily, making it technically useless in direct sunlight. That said, the green nock over a green LED is a great combination for an evening hunt.
- An orange LED is a good alternative to red as it is more of a peripheral vision color (hence why any lights on the sides of vehicles are orange.) Orange is also a great color for African hunting. During the dry season, the African background is sand with a red undertone.
- A yellow LED over a clear nock is one of the few lighted nocks combinations that can work great in darkness on an icy background.
- A blue LED is a great color for pure darkness, when there is no visible light around. The piercing nature of police cars, both red (see above) and blue, is evidence of this fact.
- For those with color blindness (red and green), however, we recommend a yellow or blue nock on a green LED.
- As for our more unique colors, for invisibility*, we recommend using “wood” for target outdoor while “smoke” for target indoor. Since our target systems turn off after 17 seconds, any LED color can be paired with these nocks. *The LED color is for you alone to observe your arrow flight while the nock color is to ensure competitors cannot see the arrow afterwards. Smoke disappears in fluorescent lighting while wood has a redder tint for perfect camouflage.
Firenock LLC is located in Henry, IL USA. In addition to its main components being made in the USA, Firenock lighted nocks are designed, packaged, and assembled in its Henry Illinois USA facility.
Here is a list that ranks the lighted nock system -- nock + circuit + battery + ESEC -- from lightest to heaviest.
- "G" Style : ~20 grain
- "A" Style : ~23 grain
- "E" Style : ~25 grain
- "F" Style : ~31 grain
- "F+" Style : ~48 grain
- "S" Style : ~27 grain
- "V" Style : ~30 grain
- "C"/"U"/"Y" Styles : ~32 grain
- "U+" Style : ~47 grain
- "D"/"D2"/"J"/"M"/"Q" Styles : ~33 grain
For the standard size circuit boards, there should be a letter (H/T/I) on one side of the circuit; H = Hunting, T = Target, I = Intermittent. The N/K series are for the slim arrows to fit the Firenock A and E style: the N series has an "H" = Hunting while the K has a "T" = Target. In the case of the ultra-slim G series, there are the Z/0 series which the "Z" letter on the circuit board means it is Hunting, and the 0 series has the T = Target. If there is no letter on the circuit, the easiest way is to know its function is to activate it.
There are three groups of Firenock lighted nock circuit sizes. Within each group, the circuits are interchangeable with any available style. The most common size of circuits, H/T/I, fit "C", "D", "D2", "D3", "F", "J", "M", "Q", "S", "U", "V", & "Y" style nocks. For slimmer arrows, the N (hunting) and K (target) circuits fit "A" and "E" style nocks. And lastly, for ultra-slim arrows, the Z (hunting) and 0 (target) circuits fit "G" style nocks.
In physics, the unit for acceleration is "g" or namely "g-force". It is usually used in aircraft and rocket science.
GA, GE, GF and GS are now referred to A3h-R, E3h-R, F3h-R and S3h-R. See this page for more information on what these codes mean.
Firenock's Lifetime Refresh / Upgrade / Side-Grade Service will let you get the latest version of Firenock lighted nock with only a small cost.
As of August 2017, lighted nocks are legal for use during archery hunting season in every state in the USA. For more details on the latest regulation updates, see below.
2010 update: It is legal to use lighted nocks in North Dakota.
2012 update: It is legal to use lighted nocks in Wyoming.
2013 update: It is legal to use lighted nocks in Washington.
2014 update: It is legal to use lighted nocks in Colorado.
2015 update: It is legal to use lighted nocks in Oregon.
2017 update: It is legal to use lighted nocks in Montana.
As of August 2014, the use of any lighted nocks for harvest is recognized as legal for the P&Y Harvest Record Book.
For 2009 or later Firenock lighted nock system, the circuits are UV cure epoxy-coated for waterproofing, however if the Firenock lighted nock is continuously submerged in water without a Hydro™ bow-fishing adaptor, its runtime will drop as water is discharging the battery.
Simply put, the answer is no. We highly discourage shooting groups. Though the Firenock integrated circuit (IC) can withstand a lot of force, there is a limitation to that resilience. The Firenock IC was designed, tested, and proved durable after several direct collisions with materials ranging from sand to concrete, ;handling 30'000 pounds per square inch at impact. But, all that aside, note that those collisions were indeed only of a "direct" nature. Because the tail end of an arrow will swing to expel excess energy after impact, multiple arrows shot near each other (like, for instance, in a group) can and often will "side slap" one other. And as the phrase suggests, an impact from the "side" is not what Firenock is designed and proven against. Such a hit will result in the IC being lifted off the circuit board and rending the Firenock circuit useless.
Of course, if such a hit and/or injury occurs to your Firenock before the warranty period of 30 days ends, send your broken Firenock circuit our way for a replacement.
See GQ17. As mentioned, to completely waterproof your Firenock, we recommend one of our two bow-fishing adapters. However, to increase the water-resistance ability of normal arrow and crossbow arrow Firenock lighted nock system, the use of string wax on the nock cylinder will do wonders.
Unlike any other lighted nock, you can easily field change the polycarbonate nock, circuit, and/or battery of our Firenock lighted nock system. It is recommended to replace a nock whenever it has passed through an animal to avoid breakage from scoring via bone (particularly during low temperatures i.e. under 4° F). For those who do not hunt, still replace your nocks every three to five years (dependent on use; being a clear, translucent nock, it is easy for UV light to degrade the plastic).
The Target (T) Firenock lighted nock system uses the same "G-Switch" technology as in the Hunting Firenock lighted nock, but will automatically turn off 17 seconds after activation instead of staying continuously lit. It is the only lighted nock system which is approved for use at ASA and IBO shoots. Why 17 seconds some might ask? 17 seconds is our "special" or perfect number because it allows you to see your arrow's flight from start to finish without it influencing your next shot (or helping your competitors' shots!). You can also use the Target lighted nocks during practice to refine your aim. Also, note that Target lighted nocks are the same weight as Hunting (H) and Intermittent (I) lighted nocks, so you do not need to re-tune your bow if you decide to exchange from one system for another within the same shaft.
The Intermittent (I) Firenock lighted nock system "G-Switch" technology as in the Hunting Firenock lighted nock, but will stay lit for 6 seconds, and then blink until the battery runs out or is manually turned it off. Why should I buy a circuit that blinks instead of stays lit, one may ask. Well, put simply, you can see it better. When a light blinks, something called a "halo effect" occurs. Think of a flare. Its purpose is to create a pulse of light to, hopefully, catch someone's eye. Reduce the degree of a flare's effects and repeat it 30 times a minute and you have our Intermittent Firenock system. Best for ground-blind hunting. Also, note Intermittent lighted nocks are the same weight as Hunting (H) and Target (T) lighted nocks, so you do not need to re-tune your bow if you decide to exchange from one system for another within the same shaft.
Firenock does not make Parker Capture nock, as it is a nock made by Parker. However base on the string diameter of 0.145” and Internal diameter of a standard crossbow arrow of 0.300”', Firenock Q style nock not only will work but work better and safer. Firenock US patented clip and lock system, which the Q style nock features not just hug the string using a set of prongs like the “Capture” nock, Firenock Q clip onto the string and make dry fire due to string misalignment nearly impossible.
Firenock does not make TenPoint Omni nock, as it is a nock made by TenPoint. However based on the string diameter of 0.155” and Internal diameter of a standard crossbow arrow of 0.300”', Firenock J style nock not only will work but work better and safer. Firenock US patented clip and lock system, which the J style nock features not just hug the string using three sets of shallow prongs like the “Omni” nock, Firenock J clip onto the string and make dry fire due to string misalignment nearly impossible. For 2019, due to the more extreme string angle of the TenPoint, and some Horton crossbows, we have tested and proof that Firenock “J” style not only work well with most of the crossbows made by TenPoint, WickerRidge, Horton, Mission, Native, Killer Instant, that has 0.155” +/-0.005” serving. The only exception to this rule is the Mission 400 which after extensive testing we are convinced that only metal nock with a flat center and side lip work best.
O-rings are NOT interchangeable. As it is easy to mix up O-rings, we recommend simply ordering O-rings according to your nock style.
The answer is yes, Firenock "S" style lighted nocks can be used, but it will take some work as the FOB has a lip that goes right between the Nock neck and the shaft which causes FOB to not be able to be used with most lighted nocks. If you would like to modify your equipment to still use FOB with our Firenock lighted nock system, follow the steps below carefully.
- Shave off a tiny edge from the back of the shaft. A pencil sharpener will do the job. This is to create a groove between the nock and the shaft. After sharpening, it is recommended to use the Firenock APS to square the end, and Drill the FOB lip hole with a 9/16">remove the lip). You want about 0.055-0.065" of material left on the lip of the FOB
- Install the Firenock into the arrow. Slide the modified FOB over the nock carefully. It will go over the Firenock and will now rest over that groove between the nock and the shaft. When shot into an animal, the FOB will move backwards and over the Firenock lighted nock without popping out and harming the Firenock (as it is proven to do without these modifications).
Yes, however it must be installed before the end cap is installed.
First and foremost, check out and try the Firenock Arrow Component Selector tool. It determines your nock style and more from your arrow type, arrow year, and crossbow manufacturer. With the release of 500fps crossbows in the past couple years, however, crossbow nock fit depends on crossbow model more than ever.
Cams, or more specifically limbs, are never perfectly synced. Full-railed crossbows, the most common crossbow, help guide a bolt down the rail by adding down pressure via a bow string and/or an arrow retainer. Manufacturers notably equip factory bolts with half moon/crescent or flat nocks to take advantage of this accuracy while remaining cost-effective. Firenock, however, recommends clip-on nocks for all types of crossbows to achieve a higher level of accuracy and safety. But what throat size and fit condition work on full-railed, railless, and semi-railless crossbows?
For a full-railed crossbow, a nock should fit loosely (0.002” to 0.005” of slack). As aforementioned, accuracy will suffer if the nock is too tight and premature sting wear will happen. We define a semi-railless crossbow as one where the only point of rail contact after launch is the front of the rail. A railless crossbow is one where there is no rail, and therefore the only point of contact at launch is the arrow rest. With this understanding, without a rail to guide the bolt, both semi-railess and railless crossbows require tight nocks that move with the bow string to guarantee consistency (0.003” to 0.007” of compression).
Another variable to consider when investigating crossbow nock fit is string quality and construction. In a perfect world, all strings are served at a high and consistent pressure. Unfortunately, strings are built by different people, machines, and businesses which all use different standards and techniques. Certain servings are tight enough that they can deform nocks and others are loose enough that they can be deformed by nocks. Always check and double check your string servings before and after shooting for accuracy with Firenock crossbow nocks.
We offer two common battery models (BR, and BL) to provide options for different hunters who hunt in different conditions (i.e. different lighting and/or temperatures.) In general, BR, giving the brightest light, is our hunting season battery but has a shelf life of nine months. BL is our year round battery and has a shelf life of two years. Lastly, BU is our "back-up" battery with a shelf life of 7 years and dimmer brightness. To learn more about each batteries' charatestic, click here
Like all electronics, poor battery connection is the number one cause of failure. Follow the troubleshooting procedure below.
- Remove your Firenock lighted nock system.
- Exchange the current battery with one from another system that you know works.
- If that doesn't work, click contact us.
We recommend the use of a battery tester. Unlike a volt meter, which only shows the battery's voltage output, a battery tester shows the true remaining power within a battery. For Firenock batteries, even when they are 90% drained, the volt meter may still show that it is 3.0v. We recommend GB Instruments™ GBT-500A Battery Tester which can be purchased from Amazon and at most local hardware stores (ACE Hardware, Menards) for about US$10.00. To test a Firenock battery with this battery tester, set the dial to "LITHIUM 3V", place the red probe (positive) onto the shell of the battery and the black probe (negative) onto the pin of the battery.
Our BR battery only has about 8 to 12 months of shelf life. It is meant for one season of use, therefore there is no need to store and then re-use the BR battery. After one season, please remove the BR battery from your arrow shaft and Firenock circuit, otherwise the BR battery may leak and ruin the lighted nock system.
Our BL and BU batteries have 36-month and 84-month shelf lives respectively. Firenock lighted nocks, like all electronic devices, drain a small amount of power continuously from the battery when it is installed, even when not in use. Thus, if not removed, the battery will be completely drained within 9 to 12 months. We recommend removing and storing a BL or BU battery if it is not going to be used for 3 or more months in its original battery case and in a cool place (e.g. basement).
When a Firenock battery is installed into a Firenock lighted nock system, some energy will always be in use due to monitoring (your Firenock lighted nock will be ready for activation at all times). In general, no matter what type of Firenock battery you use, the battery is only good for about a year if keep installed on the circuit. Thus it is recommended to remove the battery after each hunting season and put it back in the case for reuse (except for BR as it has up to 12 months shelf life).
Three tiny battery pin O-rings come standard with all Firenock battery packs. It is important for insulation and shock absorption. If you lost your O-rings, they are available here.
Though a 435 sized battery does last longer, it is about 50% heavier than the 425 sized battery. With the Firenock lighted nock system lasting at a minimum of three weeks with the use of the 425 sized battery, we found that there is no need to upset the FOC with the extra weight of the 435 sized battery.
Extreme Shock End Cap FAQ
YES, absolutely. As of 2014, all Firenock lighted nocks come with and require an Extreme Shock End Cap no matter what speed you shoot. If you do not intentionally install the ESEC and cause the Firenock to break a second time, our warranty becomes void.
In most cases, the ESEC will be permanently installed in your arrow. Due to its light weight, you might as well leave an end cap in a arrow See EQ5 for exact weights.
If your arrow was destroyed and you would like to recover your ESEC for use in another arrow, follow these instructions carefully.
- Crush the arrow with a lineman plier as close to the ESEC as possible so that it becomes small enough to submerge in an acetone bottle (we recommend the Nugene Flask Set.)
- Let sit acetone overnight or until you see that the ESEC has fallen loose from the remaining arrow shaft.
It may be due to:
- Back pressure in the arrow shaft. Please remove the field point or broadhead to release the pressure.
- Glue residue inside the shaft. Please clean the shaft and reinstall the end cap.
There is a high possibility that the ESEC has not been installed at the proper depth. Follow these instructions for troubleshooting.
- Check to see if the ESEC is installed at the proper depth with the ESEC Installation Tool that comes standard in our ESEC packs. If it is at the proper depth, the installation tool should be screwed in flush with the back of your arrow.
- If the installation tool is not flush with your arrow and your ESEC is loose, then follow step 3-5. If it is not loose, see EQ2.
- Remove your field point so that the front of your arrow is open.
- Using a standard clothes hanger wire, push the ESEC out of the arrow shaft.
- Re-install your ESEC according to the installation manual or see our support page.
Here is a list that ranks the ESEC system from lightest to heaviest.
- "G" Style : ~0.75 grain
- "A"/"E" Styles : ~1.75 grain
- "Y" Style : ~1.5 grain
- "S" Style : ~1.8 grain
- "C"/"D"/"D2"/”D3”/"F"/"J"/"M"/"Q"/"U"/"V"/"Y" Styles : ~2.0 grain
Due to the tight seal that an ESEC and its O-ring creates at installation, it is crucial for there to be either no insert or a completely hollow insert installed to prevent any back pressure. Back pressure will push the glue around the curing O-ring and will ruin the system entirely. Fortunately, there are some medial measures that can be taken to relieve pressure for a successful ESEC installation.
Methods for 0.246" ID and smaller:
- Try to remove the insert without damaging your arrow.
- If that is not possible, use slow set, 2-part epoxy instead of CA glue during installation e.g., JB Weld Original 8265S.
- If you want to take a more direct, DIY approach, you will need to sacrifice a ball point pen. See the last few minutes of our ESEC installation video page for the steps.
Methods for 0.246" ID and larger:
- Try to remove the insert without damaging your arrow.
- If that is possible, drill a small through hole in the pre-installed insert. We recommend a #29 or 0.136” drill bit.
- If that is not possible or acceptable, continue the standard installation procedure but with these precautions in mind.
- Our ESEC installation tools have been updated over time with an air relief feature for this exact scenario. Check the end with the threads for a vertical slot to make sure that your tool has one. If not, take the next point even more to heart.
- While pushing the tool into the shaft, make sure to go very slowly without any twisting motions. This, hopefully, will reduce pressure from building between the end cap and the insert. Good luck!
- If you want to take a more direct, DIY approach, you will need to sacrifice a ball point pen. See the last few minutes of our ESEC installation video page for the steps.
First and foremost, the "G" ultra slim series nock is unique from all its counterparts due to its stack-based system. Every component only floats upon and fits unto one other via tension between the glued-in ESEC and pushed-in nock. Fit issues, therefore, usually arise from the ESEC being installed incorrectly, either too deep or too shallow. This error is exaggerated when a matched weight is installed as there is no O-ring like on the lighted circuit/battery combination.
- To solve the loose fit issue (e.g., rattling), add a tiny amount of cotton from the tip of a Q-tip or cotton ball to fill the gap. We recommend adding cotton in small increments to not add too much material.
- To solve the tight fit issue (e.g., nock doesn't sit flush with the arrow), carefully sand the bottom end of the matched weight tool until every component fits comfortably. Again, we recommend working slowly and carefully to not take away too much material.