This British Standard specifies requirements for dial gauges with the
plunger movement parallel to the plane of the dial.
The standard is applicable to gauges having dial diameters from
47.6 mm or 17?8 in to 63.5 mm or 21?2 in, as measured from the outside
of the scale marks, and scale divisions of 0.01 mm, 0.001 in (sometimes
sub-divided into half divisions of 0.000 5 in, in which case they are
commonly designated “0.000 5 in gauges”) or 0.000 1 in.
NOTE 1 Attention is drawn to the fact that the metric dimensions are
not necessarily direct conversions of the imperial dimensions.
NOTE 2 Recommended dimensions for dial gauges are given in Annex A
(Figure A.1) and notes on methods of testing and on the care and use of
dial gauges are given in Annex B and Annex C respectively.