ITW Ramset powder actuated fasteners are specifically fabricated to meet the exacting requirements of toughness and durability that enable them to penetrate dense concrete and structural quality steel Designed for use in concrete and structural steel applications Washer increases bearing surface against the material to be fastened Square washer indicates 3in pin has been installed 16 gage metal washer 3in shank length .145 shank diameter .300 head diameter 100 per box