Designed specifically for the Trijicon RMR. This lightweight Lower 1/3 Co-Witness mount is perfect for mounting the RMR/SRO on any rifle platform with a Picatinny rail. The AC32075 provides a Lower 1/3 Co-Witness with backup iron sights. This means that the RMR/SRO is mounted higher than the iron sights resulting in a clearer field of view. The iron sights remain visible in the lower 1/3 of your optical window for use as a backup.