The Leupold 180949 model features BackCountry cross-slot bases that are skillfully machined from 7075-T6 aircraft-grade aluminum. This not only ensures lightweight but also provides rugged performance. The base is compatible with both Picatinny and Weaver-style rings. Leupold\'s 2-Piece Backcountry Scope Mounts with Integral Rings are crafted from light yet robust 7075 aluminum. These top-notch precision machined mounts are a hybrid of the traditional base and the ring, designed to fit directly on the rifle receiver. This innovative mounting system is not only easy to install, but also incredibly stable. It comes in a matte black finish, and its specifications include a medium height, integral scope ring style, a two-piece structure, and a tube diameter of 1.