While there are actually two types of AeroInsert*, only one is a part of the AeroSystem line—AeroInsert-A (AIA). And although AIA cannot be used in the AeroConcept System, its design and characteristics are not only essential to AeroInsert-H, it is a great standalone component for those who prefer a straightforward system.
AeroInsert-A boasts Reverse Tapered Shoulder Technology (US Patent: 8,403,777).
What does such a technology entail? First, consider the name. On any insert, whether it’s standard or a half-out, a portion remains outside the arrow. We call that portion a “shoulder,” which most significant part is where it meets with the front of a shaft. For after repeated use, any disparity in pressure at that contact point can cause mushrooming and/or splintering. There are two main reasons for these outcomes  inconsistent insert and/or shaft sizing (i.e. if one is narrower or wider than the other, pressure can be distributed incorrectly) and  uneven squaring (i.e. if both are not perfectly square, one or both can shift around and, again, distribute pressure irregularly). And, unfortunately, no matter how closely matched the sizing or how thorough the squaring, arrow failure has proven inevitable.
But what if those causes could never come into effect in the first place? What if, instead of trying to avoid their causes, they could be used as an advantage? With Reverse Tapered Shoulder Technology, such is a reality. By simply preparing an arrow with a 45 degree chamfering (see our recommended Arrow Chamfering Tool below), an AeroInsert-A with a reverse 45 degree tapering can mate with it. Repeated use will only benefit concentricity—as energy and pressure from launch and/or impact transfer(s) the arrow sits and locks deeper into the insert. Ultimately, sizing no longer matters past ID and squaring is no longer necessary since AIA requires chamfered shafts instead.
*AeroInsert-D (AID) inserts have been discontinued and replaced by AeroInsert-H.