Wish I had bought them sooner. They helped me a lot to make a cabinet using self-tapping screws. I was able to clamp them with two corners at a time and line up the edges perfectly before clamping. Then, with a Kreg clamp in one of the four holes, I was able to screw in the other 3 screws without shifting, then remove the clamp and drive in the last screw. It used to be difficult to keep the edges straight. I'm a simple carpenter with the usual basic tools and all of these squares measured…