The 3/4" Type BY High Friction Clamp is designed to be used in applications that require higher tensile and frictional capacities than standard clamps. It may be used with parallel or tapered flanges. The recess in the top of the BY will capture the head of an A325 bolt. When using nut and washer on top of clamp, the BYP should be used to fill the recess. See chart below for tail length and packing combination to match flange thickness.