Sig Sauer Electro-Optics Alpha2 1-Pc Base & 30mm Ring Combo For MAR Rifle Flat Dark Earth Anodized Finish 6061-T6 Aluminum 0 MOA Sig's Alpha2 Scope Mounts are machined with an exactness that is both strong yet ductile which allows the rings to form around a riflescope, yet will not damage scope under proper installation. The rings are epoxy powder coated to prevent oxidation and resist gun oils, cleaning solutions, and outdoor exposure.