Section 7(2) in The Punjab Weights and Measures (Enforcement) Act, 1958
(2)Any custom, usage, practice or method of whatever nature which permits in any trade a trader, seller or buyer to demand, receive or cause to be demanded or received any quantity of article in excess of, or less than, the quantity fixed by the weight or measure by which the contract or dealing in respect of the said article has been made, shall be void.
