BS 959:2008 PDF

1   Scope This standard specifies requirements for internal micrometers comprising a measuring head, extension rods with or without spacing collars, and, in the smaller sizes, a handle. Provision is made for three sizes of measuring heads, in both metric and inch units, as shown in Table 1 and Table 2.

NOTE Attention is drawn to the fact that metric dimensions are not necessarily direct conversions of the imperial dimensions.

Table 1 — Measuring heads — metric measurements

Size of head

Length of graduated scale on barrel

Usual ranges of the instrument when used with extension rods