Applies to slip gauges of rectangular form in inch sizes up to 4 in. and to the commoner types of accessories used with such gauges, viz. measuring jaws, scribbing point and centre point holders (or slides) and base. Provision is made for slip gauges of the reference grade of accuracy in addition to the three grades: workshop, inspection, and calibration. Recommended sets of gauges are given in an appendix. For metric gauge blocks see AS 1457.