Troy Industries, Inc. Rear Fixed Battle Sight. This baby gives you the edge for on - target shots! Replace your factory M4A2 rear sight with this extremely durable Fixed Battle Sight! With hardened aircraft aluminum and steel construction, these babies are reliable for in-the-field shooting. Won"t pop up and won"t get knocked out of alignment so when you"re ready to fire, you don"t have to mess with adjustments. Battle-ready! Hammer it home: Permanent rail mount is an alternative to the standard A2 rear sight or carry handle; Provides constant access to fixed sights that continuously hold their zero; Fits all M4, M16, AR15, AR10 and other firearms that have a flat-top receiver. State Color. Get yours here, for LESS! WARNING: You must be 18 or older to purchase Assault Rifle Parts. Assault Rifle Parts cannot be shipped to CA; Chicago, IL; New York City; NJ; D.C.; MA; Canada or Puerto Rico. Please check your State, County and City laws for restrictions before ordering Assault Rifle Parts. Troy Industries, Inc. Rear Fixed Battle Sight