Review on Fladess Degree Position Squares: Achieve Accurate Measurements Every Inch by Bill Dahl

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 perfect 90 degrees with all my squares. I don't know if the tolerances are good enough for precise metalworking - probably not even if they were necessary, but I can't know. They're certainly good enough for any wood tolerance and seem pretty solid. I'll probably buy more in the future, but for now, while it may be good, I really don't need more than four.