Accu-Tac ScoScope Rings 30mm High (Clears 56mm Lens) Black Finish HSR-300 The Accu-Tac Scope rings are Precision CNC machined to very tight tolerances on the height, center-line, and tube bed arch. For perfect alignment of the scope it utilizes a built in bubble level for perfect leveling of your rifle, and high strength hardware for durability. Specifications: - Materials: 7075 Aluminum Alloy - Height (center of tube to base): 1.39” – 35.3mm - Height (bottom of tube base): .800” – 20.32mm - Color : Flat Black - Coating : Type 111 (MIL-SPEC) Hard Anodize - Weight : 6.05oz/ 172g/ .378lb - Note : Will Clear a 56 mm Objective Lens Diameter