Weaver Precision Tactical Rings represent the company's premium, highest quality optic mounting solution. Engineered for shooters demanding the ultimate in durability and accuracy, Precision Tactical Rings utilize a heavy-duty integral cross bolt providing true mechanical lock up. Giving shooters and competitors uncompromising strength under the toughest conditions, Precision Tactical models are available in 30mm and 34mm diameters, multiple heights, and are fully compatible with Picatinny rails and bases. Proudly Made in America Precision Machined 7075-T6 Aluminum Type III Hardcoat Anodized Finish Durable TorxA(R) Head Cap Screws Picatinny Mount/Base Compatible Weaver Recommended Torque Specs Cap Screws: 25 in lbs Crossbolt: 65 in lbs