Compatible with the Osprey Global Tactical 4-16x50IRF/MDG, 6-24x50IRF/MDG, and 10-40x50IRF/MDG scopes, the 7.62x39 Bullet Drop Compensator provides a preset bullet drop compensation knob for quickly adjusting for long-range accuracy. It has a user-friendly design and is easily adapted to your scope. Just zero your weapon at 100 yards and compensate by simply winding the knob counterclockwise to your distance marked on the turret.