To fit crossbows with a 0.145" serving and arrows with a 0.300" ID with triggers / anti-dry-fire (ADF) systems that require a long-pronged design.
Available in 18 colors / shades (3 nock colors x 6 LED colors)
Full system, on average, weighs only ~32 grains
Ready for the only target lighted nock system that is IBO & ASA approved: Firenock “T” circuit
Ready for hunting and intermittent lighted nock systems that stay lit / blink for up to 21 days with a BL battery powering a Firenock “H” / “I” red circuit