Red Dot Mounts

A red dot mount decides two things that matter more than the dot itself: height and footprint. Height sets where your head has to be for the dot to appear, and on a carbine the lower-third or absolute co-witness choice determines whether your iron sights sit at the bottom of the window or in the middle of it.

Footprint is the compatibility trap. Trijicon RMR, Docter/Noblex, Shield RMSc, Aimpoint ACRO and Holosun's various patterns all use different screw spacings and recoil lug positions, and they are not interchangeable. Check the footprint your optic uses and the one your slide or mount is cut for before ordering, not after.