?Our most popular heavy-duty steel bar clamps.FEATURESThe special steel I-bar design is tremendously strong and stiff, and the clamp head is fixed for maximum resilience.A cold-drawn steel screw with smoothly cut acme threads attaches to ductile cast-iron castings to complete the clamp.Depend on this clamp to withstand the rigorous daily demands of school shops, commercial woodworking operations, metalworking factories, welding applications, and serious woodworking applications.