1.1 This specification establishes allowable limits for the various types of surface discontinuities that may occur during the manufacture and processing of metric-series nuts with nominal diameters 5 mm and larger and inch-series nuts with nominal diameters 1/4 in. and larger. 1.2 The values stated in either SI (metric) or inch-pound units are to be regarded separately as standard. The values stated in each system are not exact equivalents; therefore, each system must be used indepe