The unique golden yellow color of these right angle clamps immediately catches my eye. The typical color seems to be red or blue to copy two other very popular brands. Since this is gold, the graduations must be done in black ink, not white, as they are very difficult to see. I have not found any quality control issues with this set. The set was packaged very well and when I opened the box everything was in place. The photo I took was taken right after opening the box and is very impressive. Each 90ยบ angle fits perfectly in all holes of each corner block. The aluminum stops that grip the opposite side of the tree are perfect for the elbow, as is the threaded quick-release handle. No problem. I also compared both corners with several shop squares and they were perfect in every test. No complaints or problems in the quality department. I'd like to give this product a three star rating rather than four because the white spots are so hard to see, but ultimately I don't mind. just as I don't use a clumsy piece of aluminum for my measurements. Even if it were me, I don't see why I would need to measure anything with these clamps. Clamps good and tight, no problems. I will rate my standard 4 stars as they are very nice to have in store.