Leupold Mark 4 30mm Scope Rings - These rings are machined from aircraft-grade aluminum, they offer superior integrity and tighter tolerances that are based on the proven cross-slot design. Use Leupold PRW bases or any other Picatinny-style mount rails. Accommodates both the oversized 8-40 screw and a 6-48 screw; Securely attach your scope to any M16 variant with a carrying handle using this rugged mount; Delivers rock-solid stability for repeatable accuracy; Use with LeupoldA(R) QRW(TM) mounts; Secure your Mark 4A(R) CQ/TA(R) scope to any Picatinny-style mounting rail using this specially designed mounting bracket; Two rugged cross-slot bolts secure the bracket for rock-solid durability; Ring Diameter: 1.18in; Ring Diameter: 30mm; Height: 1.06in;