This specification has been declared "CANCELLED" by the Aerospace Materials Division, SAE, as of July 2007, and has been superseded by AMS 2231. The requirements of the latest issue of AMS 2231 shall be fulfilled whenever reference is made to the cancelled MAM 2231B. By this action, this document will remain listed in the Numerical Section of the Index of Aerospace Material Specifications noting that it is superseded by AMS 2231.

This specification covers established metric manufacturing tolerances applicable to carbon steel bars ordered to metric dimensions. These tolerances apply to all conditions, unless otherwise noted. The term "excl" is used to apply only to the higher figure of the specified range.

No clear cut demarcation is available to differentiate between bar and wire products, therefore definitions of these products are not included.