Feature 20 MOA Type, AR Platform Tactical Picatinny Mount, Four Screws Per Ring 38mm 1.5" Bottom to Ring Center, Extremely Accurate w/ Full CNC Machined Light Weight, 21mm Picatinny Mount with Two Crossing Bolts & Anti-Retreat Bar Specification Ring Diameter: 30mm Overall Length: 139m / 5.5" Overall Height: 62mm / 2.4" Mount Length: 120mm / 4.7" Ring Width: 46mm / 1.8" Central Height: 38mm / 1.5", bottom to center Ring Length: 21mm / 0.8" Gap Length: 73mm / 2.9" Material: 6061-T6 aluminum alloy Weight: 155g / 5.5oz Mount: 1913 Picatinny Finish: Black matte Screws per ring: 4 High-durability aluminum alloy in black matte Do not use over 18 inch / pounds of torque on the scope rings&'; screws Suggest 25 inch / pounds (Can Accept Max 45 Inch / Pounds) torque force for big nuts when installing the mount on the picatinny rail 20MOA one piece mount designed for hard and rigorous use With hex key and retail package, hex key can be used to fasten the clamp nuts Relations 30mm 1-Piece Extended Picatinny AR Mount 30mm 1-Piece Extended Picatinny AR Mount Coyote FDE 30mm 20MOA 1-Piece Extended Picatinny AR Mount Coyote FDE