Relates to a range of self-holding tapers selected from the Metric, Brown and Sharpe, and Morse series. Standard basic dimensions are given for the complete range and the tables of general dimensions and tolerances provide for self-holding tapers of the following types: tanged; tapped end; and plain end. Tables of general dimensions and tolerances for sockets for all types of shanks are also included. Section Two provides for a series of plug and ring gauges for the verification of self-holding tapers in machine tool spindles and sleeves and on small tool shanks.