# The Weights and Measures Regulations 1963, Regulation 50


(1) In the case of weights of the flat-circular type made of iron, the lead inserted for adjustment shall be not less than one-eighth of an inch in thickness; the approximate depth of the adjusting hole shall be equal to three-fifths of the centre thickness of the weight; and the approximate minimum distance of the lead from the surface of the weight shall, when new, be one-fifth of the centre thickness of the weight.
(2) The adjusting holes in such weights shall be circular and their smallest diameter shall be approximately—
(a) in the case of weights of a purported value of 4 pounds or 2 pounds, 1 inch;
(b) in the case of weights of a purported value of 1 pound, three-quarters of an inch;
(c) in the case of weights of a purported value of 8 ounces or 4 ounces, half an inch.

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Source: https://www.legislation.gov.uk/uksi/1963/1710/regulation/50 (the official version)
Page: https://openlegislation.uk/weights-and-measures-regulations-1963/regulation-50
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.