SAMB03 bipod slides onto European Anschutz stock rail and clamps with a knurled thumb nut. Use the bipod to rest your gun instead of scratching it when you set it down on the ground The legs are made of carbon steel with rubber ball end caps and the top block is made of aluminum alloy. Width of top block measures at 13mm. Inner opening at the bottom of the legs measures 4.5inch and height from bottom to top measures 4.25inch. Weight: 2.6oz. Finish & color: Anodized black.