I am looking for a square that is "square". I purchased 2, a very small one from Axminster (when I ordered few things from there) and one from Amazon (Kinex). Returned the Kinex (not square) and purchased the Shinwa from AMZ again. The Axminster and the Shinwa do not square in the inside. I tried the straight edge and perpendicular to the straight edge and then flip exercise and it looks like the Shinwa is off. The Axminster is only 3.5" so the error might be so small that I cannot even see it when I do the same exercise. So back to square one...Beside the Starrett (which I have no money for) is there any other decent square (BS 939 Grade B should be enough) to check my squareness. I saw old post on this topic but what was good years ago might be awful now because of saving money in Quality Control and increase of outsourcing. Thanks