law: Standards of Weights and Measures (Enforcement) Act, 1985
  Chapter III: General
  
  Provisions in Relation to Standard Weights and Measures
  9. Prohibition of use
  
  of weights and measures other than standard weights and measures.-
  1.  Notwithstanding
  
  any custom, usage or method of whatever nature, no weight or measure, other
  
  than the standard weight or measure, shall be used or kept in any premises in
  
  such circumstances as to indicate that such weight or measure is intended, or
  
  is likely to be used, for any weighment or measurement.
  2.  On
  
  and from the commencement of this Act, no weight, measure or number, other than
  
  the standard weight or measure shall be used in, or form the basis of, any
  
  contract or other agreement in relation to any trade, commerce, production or
  
  protection.
  3.  Any
  
  contract or other agreement, which contravenes the provisions of sub-section
  
  (2), shall be void.