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Foldable rear sight for M4/M16 series. Suitable for 20mm RIS/RAS rails.
Some guns don’t come with a rear sight, or only have them integrated into the carry handle. BUIS (Back up Iron Sights) are, as the name suggests, a back up. Having them to hand is useful should your optics run out of battery etc.
Constructed out of metal, this flip up sight is easy to mount – just use the allen key provided to loosen the bolt & slot it into position on your rail, and tighten it down! There are no fiddly latches etc – just fold it down out of the way until you need it!
