The Helos BTR 1-4.5x24mm Riflescope by Athlon Optics was specifically designed for AR platforms, but is highly compatible with other service rifle types as well. It comes equipped with an illuminated ATSR3 second focal plane reticle, which features a 0.5 MOA dot in the center of a 12 MOA circle and hold over points to compensate for bullet drop. The Helos BTR also sports exposed turrets for quick adjustments to windage and elevation, and its Precision Zero Stop System allows the user to rapidly return to the original zeroing. In addition, the riflescope’s elevation turret comes with the Revolution Lock system, which limits the Up adjustment within one revolution of the original zeroing. Features of the Helos BTR 1-4.5x24mm Riflescope: Exposed TurretsAllows for quick adjustments to windage and elevation Revolution LockLocks down original zeroing position and enables the user to dial back to it in one turn. This feature eliminates any doubts on which turn is dialed upEtched Glass Reticle Provides better backing support for complex reticle designs and greater recoil resistance ATSR3 Reticle Features a 0.5 MOA dot in the center of a 12 MOA circle and hold over points to compensate for bullet drop. Illuminated Reticle Provides greater visibility in low light environments athlon optics Athlon Helos BTR 1-4.5x24mm Exposed Turrets Zero Stop ATSR3 SFP IR MOA Riflescope 214101