Sig's Alpha2 Scope Mounts are machined with an exactness that is both strong yet ductile that allows the rings to form around a riflescope, yet will not damage scope under proper installation. The steel rings are epoxy powder coated to prevent oxidation and resist gun oils, cleaning solutions, and outdoor exposure. It features steel Weaver-style clamps. This model has 30mm rings, 20MOA and black finish.