Sight Mount for Trijicon® RCO-ACOG & Reflex Sights on M1913 Picatinny Rail. General Features:? For use with Trijicon® ACOG & Reflex Series Optical Sights? Eye-Relief Enhancement: 3.5" – Adjustable in 3/8" increments? Retains Zero under extensive live fire usage and while subjected to harsh mechanical stresses: .01 MOA? Returns to Zero following repeated removal-remount cycles during extensive live fire usage: Value: .01 MOA [Lab Tested] < .20 MOA [Live Fire]? Adjustable to Out-of-Spec / Worn M1913 Picatinny Rails? Auto-Locking Quick Detach™ (ALQD™) Lever System? Non-Abrading / Gouging Picatinny Rail Lockdown Feature GDI Mounts GDI R-COM E-Model Combat Optic Mount RCME