Quick-release clamps are designed to fit into the T-slot on the bottom of the track saw guide for secure positioning It really speeds up changeovers compared to tightening and loosening screw-type clamps And can be used with dog holes or channels on an table to secure workpieces for cutting, grinding and milling. Ratchet mechanism: Ratchet mechanism can be easily locked and quickly released These ratchet clamps are effortless and you can work faster and longer with them., Weight: 1.0582188576 pounds, Manufacturer: Eioeeklop