The Trijicon RMR sight is a very popular choice as a secondary sighting system, either offset on AR-15s or tactical shotguns or piggy-backed on higher magnification optical sights. They manufacture a wide range of Trijicon RMR mounts to suit these applications. They are made of 6061 T-6 aluminum, Type III anodized in a matte black surface with fixings made of steel, phosphated to a matching finish. Some of the most popular mounts in the range are as follows:
RM33 is a low RMR Picatinny mount to put the Trijicon RMR as low as possible on a Picatinny rail. This is typically desired on tactical shotguns. Two allen headed bolts clamp the mount to the Picatinny rail and a steel cross bolt prevents movement backward or forward.
The RM34 RMR mount is a high Picatinny mount for use on AR-15s and similar rifles and carbines. This RMR Picatinny mount uses a steel thumbscrew with a cross-slot to aid further tightening. Depending on the sights selected, this mount will either lower third or absolute co-witness.

Trijicon RM34W Weaver mount
The RM34W RMR Weaver mount is a low Weaver RMR mount for use on hunting rifles and others still using the Weaver standard rail system. It is otherwise identical to the RM34 RMR Picatinny mount.
The RM36 RMR ACOG mount enables you to piggy-back the RMR on 1.5X, 2X and 3X Trijicon ACOG sights. An RMR ACOG piggy-backed setup enables an instant switch from close range to longer range engagements.
The RM55 offset Picatinny rail attaches to the Mil Std 1913 Picatinny Rail on your rifle, carbine or shotgun and offers a small section of Picatinny rail of the correct length to take an RMR reflex sight on an appropriate mount. The RM55 offset Picatinny mount clamps onto your Picatinny rail with a steel thumbscrew and steel clamping surface. The thumbscrew is slotted to be tightened with a tool and a crossbar stops movement fore and aft.
Check the price of Trijicon RMR mounts at Brownells, a name you can trust.
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