Feature Quick Release Weaver Scope Rings, 30mm Diameter, 20.3mm (0.8in) Center Height Low Profile 4 Torx Screws Per Ring, Accurate with CNC Machined, Solid Steel Construction Fit On 21mm Picatinny and Weaver Rails Specification Ring Dia: 30 mm / 1.2 in Height: N/A Central Height: 20.3 mm / 0.8 in (Bottom to Center) Length: N/A Material: Steel Weight: 176 g / 6.2 oz Mount: Picatinny and Weaver Finish: Black Matte Items in the Package: T15 Torx Wrench, Hex Key Size