They are cheaper than Starrett squares but not as good as Starrett. I have 2 sets, a 12" and a 6" combo square. The 12" was perfectly accurate, but I had to adjust the 6" with a file to get it right. That disappointed me, but I can live with that. What's even more frustrating is that they're difficult to snap into place. I really have to turn the little knob to keep them in place. Getting the square in the right position only to have it drift as I use it is frustrating. If you can't afford better, these are acceptable, but they're by no means best in class.
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