Columbian 27300-15 piece Professional Clamp set The Slip Clutch Bar Clamp with ratcheting clutch allows jaws to quickly secure and release the work piece. Slip Clutch Bar Clamps include plastic pad covers to prevent marring the work piece. The Nylon Spring clamps are made of lightweight high impact resistant nylon. The package includes 3 sizes of Nylon Spring clamps to suit all clamping needs. The Mini Bar clamps are designed for clamping operations in tight areas.