law: Standards of Weights and Measures Act, 1976 
  32. Use of weights
  
  only or measures only in certain cases. - 
  (l) The Central
  
  Government may, by rules made in this behalf, direct that in respect of the
  
  class of goods or undertakings or users specified therein, no transaction,
  
  dealing or contract shall be made or had except by such weight, measure or
  
  number as may be specified in the said rules.
  (2) Any rule made
  
  under sub-section (1) shall take effect in such area, from such future date and
  
  subject to such conditions, if any, as may be specified therein.