Replaces OEM scope cap with 35Adeg offset mounting surface, for Holosun 509T footprint. Ambidextrous with SCRS. Fits Geissele Super Precision and Reptilia AUS 30mm / 0 MOA mounts, 1.535" height. Compatible with Holosun 509T and SCRS. Places 509T at same height over bore (2.75") as primary optic. SCRS will sit higher. Note: if you are concerned with clearing a large windage turret (such as Trijicon Credo), we recommend model H30 with Holosun's SCRS, or T30 using Holoson's 509T to RMR adapter plate.*Red Dot Not Included*