Bessey I-Beam bar clamps are perfect for gluing up large panels and table tops, while minimizing deflection and the resultant panel bowing. Each clamp features an I-beam bar made from heavy-duty nickel-plated steel for exceptional strength, very little deflection and resistance to corrosion. The cast iron sliding head employs four clutch plates that firmly grip the bar stock. The cast iron clamping head features an Acme threaded screw with a large, sturdy handle that generates plenty of clamping force. All castings are powder-coated for corrosion-resistance and durability.