The double square is one of the must-have woodworking and carpentry tools.
Just like the speed square, try square, framing square, T square, and combination square, the double square works hand-in-glove to make your jobs such as squareness checking, marking, and scribing become easier. Professionals should have them all because when it comes down to it, each of them plays a unique role that makes them quite irreplaceable. The body of a double square consists of a head (handle) and a blade. The head can slide along the blade. Therefore, two things set this tool apart from other woodworking and machinist tools: firstly, they are adjustable, and secondly, they can be applied to check the squareness of corners from both ends. Speed square and try square is not adjustable.