The Vortex Viper Cantilever Mount is designed to mount optics with a rifle flattop receiver. The cantilever ring mount positions the center of the riflescope tube at a height of 1.43" form the base. The superior clamping surface area provides a sure hold on Picatinny-style rail that may even be somewhat out of spec. The mount is CNC machined from solid 6061-T6 aluminum and features a hard coat Type 3 Mil-spec anodizing for a lifelong lasting finish. Vortex Viper 30mm cantilever ring mount provides the correct height and forward placement for proper scope mounting. The cantilever ring mount positions the center of the riflescope tube at a height of 1.435" (36.45mm) from the base.