Leupold mounts are every bit as rugged and dependable as the Leupold optics they’re intended to secure. With a huge variety of mounting systems, for nearly every type of firearm under the sun, you’re sure to find the perfect match for you firearm, and your style of shooting. STD 2-Piece bases offer maximum accessibility to the breech area of your rifle. STD 2-Piece bases fit right- and left-hand actions, and reversible bases are available for many actions. Machined steel construction.