Jorgensen steel bar clamps are seriously strong. Cast-iron stationary and sliding heads with orange-powder coated finish are merged with a high-carbon rust-resistant steel bar that packs a whopping 85,000 pounds per square inch of tensile strength. The fast-acting sliding head is acme threaded to accommodate a cold-drawn steel screw with a large easy-grip handle and swivel pad. And our original multiple-disc-clutch design allows the sliding head to hold securely at any point along the bar.