Bar clamp head Set. Cramp heads are a low cost alternative to the full size T Bar and Sash Bar Cramps. A bar cramp of any length can be made by using a piece of timber 1"(25mm) thick. The timber is drilled with holes producing a light duty bar cramp as strong and as true as the timber chosen. The heads are made from malleable iron, the handle screw and pin from high quality steel for hard wearing long life. Blackened screw has rolled threads for extra strength and resistance to wear. Dimensions: 9.8 x 2.8 x 3.7".