law: Standards of Weights and Measures Act, 1976 
  80. Non-metric weight
  
  or measure not to be mentioned in any  document, etc. or to form the basis of any
  
  contract after the commencement of this Act. -
  (1)No unit of
  
  weight, measure or numeration shall, after the commencement of this Act, be
  
  stated in any enactment, notification, rule, order, contract, deed or other
  
  instrument in terms of any unit of weight, measure or numeration other than
  
  that of a standard unit of weight, measure or numeration.
  (2) On and from the
  
  commencement of this Act no weight, measure or number other than the standard
  
  weight, measure or number shall be used in, or form the basis of, any contract
  
  or other agreement in relation to any inter-State or international trade or
  
  commerce:
  Provided that in relation to
  
  any goods which are exported, the weight, measure or number of such goods may
  
  be indicated thereon, or in any contract in addition to the standard units of
  
  weight, measure or numeration, in accordance with any other system of weight,
  
  measure or numeration if the person to whom the export is to be made so
  
  requires.
  (3) Any contract or
  
  other agreement in contravention of the provisions of sub-section (2) shall be
  
  void.
  (4) No written record
  
  of the results of any measurement shall be maintained in any unit other than
  
  the standard unit of weight, measure or numeration established by or under this
  
  Act.