Talley 30mm X-Bolt Ring/Base Combo Medium 2-Piece - Talley's Lightweight Scope Mount features a unique, one-piece construction extruded from 7000 series alloy and precision CNC-machined to its final design. It has no joint between the scope and the rifle which ultimately provides more strength and durability than most steel rings and bases, but with a lighter overall weight. This model is compatible with Browning X-Bolt rifles, has a medium ring height and 30mm diameter.