The Trijicon RMR adapter is good for that situation where you need the versatility of a magnified optic paired with a red dot sight in close quarters. This offset rail adapter attaches to the firearm's picatinny rail and provides a short picatinny rail at a 45 degree offset to mount a red dot sight. By mounting a red dot at a 45 degree offset, it allows for an easy transition from the magnified optic by simply rotating the firearm. The low profile of this mount allows you to mount underneath almost any riflescope without removing the scope or rings, or in front/behind the optic. The RMR attaches to standard 1913 picatinny rails, is made of lightweight anodized aluminum and is ambidextrous for right or left handed shooters. *Note- this is just the rail adapter. In order to mount the Trijicon RMR/SRO you will need the RM33 low mount. Made in the USA.
Specifications:

Type	Adapter
Model	RMR/SRO
Dimensions	1913 Picatinny
Size
Material	Aluminum
Action	Aluminum
Trigger	1
Safety
Thread Pattern	Picatinny Rail
Finish	Black
Bolt Type	No
Hand
Hammer Type
Max Capacity