Trijicon's MRO Co-Witness Quick Release Mount is a compact, lightweight mount that provides a stable platform for your MRO reflex sight with easy, one handed, tool-free attachment to any Picatinny rail. This is the Quick-Release Co-Witness Mount that comes with the Trijicon MRO Patrol red dot sight. It lets you retain the use of your rifle's "iron" sights by viewing them through the MRO. Two models: 1/3 Lower Co-Witness and Full Co-Witness Clamps to any MIL-STD 1913 Picatinny Rail Hit the release lever to remove sight from one rifle and transfer to another Sturdy 7075 T6 aluminum alloy is strong yet light light - weighs only 1.8 oz.! F Mfg: Trijicon