They are square enough for my purposes (woodworking and scale models). They look good (to me) and feel solid. My only complaints: 1. They were filled with oil upon arrival. While this is good for rust prevention, I think they could greatly reduce it. I measured them with calipers. Ironically, the sizes used do not correspond to a straight decimal inch, architectural fraction, decimal measure, or fractional measure. See for example the attached least squares drawing. I assume this is due to the lack of precision other than the squares of the numbers. Overall these are very good squares for the price.
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