The first of its kind! Innovative, new Bench Block® Pipe Clamp Stabilizers securely hold four standard 3/4" pipe clamps at 90° for assembly of doors or frames. Set of four. Bench Block® Pipe Clamp Stabilizers can be fixed to bench or work surface to eliminate movement during clamping and prevent rotation when not clamped. Holds 3/4" pipe at 90° for doors and frames. Tightly grips pipe to prevent heads from falling over. With mounting holes for fixed jigs. Space provided for clamp head clearance. Fiberglass reinforced plastic. Patent pending.