PRECISION QR EXTENDED CANTILEVER MOUNT This quick-release cantilever mount is designed for mounting telescopic sights with 30mm tubes onto a flattop style AR-15 rifle. The offset of this cantilever mount positions the scope in a forward location, providing correct eye relief and head placement when used on an AR-15. Materials and Construction The Precision Optic Mount is precision CNC machined from a block of 6061 T6 aluminum and finished in hard coat type 3 mil-spec anodized black for a rock hard lasting finish. Precision machined from 6061 T6 aluminum. Hard coat Type 3 Mil-Spec anodized for a lifetime of performance. Note This mount positions the center of the riflescope tube at a height of 1.45 inches (37 mm) from the top surface of the Picatinny base. Ring screw bit size is 9/64" hex head. Weighs 8.9 ounces. Made with pride in the U.S.A.