WORKPRO 6"&4-1/2" Mini Bar Clamp Set Set includes: 2pc 4-1/2” bar clamps(screw release), clamping force: 50lbs. 2pc 6” bar clamps(quick-change button), clamping force: 150lbs. Bar Clamp for Woodworking A good collection of small clamps is invaluable in the workshop. WORKPRO 6"&4-1/2" mini bar clamps set can help you with your daily DIY woodworking projects like gluing and stability-holding. The characteristics of its small body become very important when come across some narrow corners. 150lbs. Clamping Force The WORKPRO 6"&4-1/2" clamps are tiny but strong enough for daily woodworking glue up projects and any woodworking DIY projects. Their small body also support one-hand operation, enhancing the sense of use and operation.