The Tasco 1 inch-to-30mm rings are rock-solid, and designed specifically for all types of modern rifles. They are engineered to handle heavy recoil, and are secured with four bolt cap screws. They can accommodate scopes with 1-inch or 30mm tubes, and are available in low, medium and high models to fit an array of platforms. Finish: Matte Specifications: Removeable 1? aluminum insert Model: TS00603 Additional Info: Angle-Loc clamping system Description: T15 torx screws, 1/2? slotted cross bolt nut