This standard applies to diemakers', machinists' and cylinder squares used in determining angles when manufacturing parts. Carpenters' squares are not included in this standard.

The squares shall be graduated in the International System of Units (SI) and/or the Yard/Pound System. If a value for a measurement given in this standard is followed by an equivalent parenthesized value in other units, the former shall be regarded as the requirement and the latter as a rounded approximation.

The testing and evaluation of a product against this standard may require the use of materials and/or equipment that could be hazardous. This document does not purport to address all the safety aspects associated with its use. Anyone using this standard has the responsibility to consult the appropriate authorities and to establish appropriate health and safety practices in conjunction with any applicable regulatory requirements prior to its use.