IRWIN Tools VISE-GRIP Clamp Set, 6-Piece (SET150) Quick-change bar clamps apply up to 300 pounds of force. I-beam bar reduces flexing and bowing. Clutch lock Allows you to adjust and release quickly. Mini bar clamps apply up to 150 pounds of force for smaller jobs. Both types of bar clamp are made from durable high-carbon steel. Resin spring clamps provide a quick, secure hold for even odd-shaped work pieces. Replaceable pads prevent marring of work surfaces. Includes (2) 12-inch quick-change bar clamps, (2) 6-inch mini bar clamps, and (2) 2-inch spring clamps. Backed by the IRWIN lifetime guarantee.