The one-piece construction of the Talley Lightweight scope mount is unique. The rigid design has no joint between the scope and rifle. The Talley lightweight design eliminates the possibility of an ?out of alignment' interface or ?loose connection? between the ring and base of traditional two-piece designs - ultimately providing more strength and durability than rival steel rings and bases but doing it with a lighter overall weight. By extruding the 7000 series alloy, know for its durability, then precision CNC machining the mount to its final design, Talley can provide you with one of the strongest, lightest mounts on the market. They offer this mounting system in 1? and 30mm.