The Standards of Weights and Measures (Enforcement) Act,1985
Section 15. Secondary or working standard which may not be stamped
(1) Where the State Government is of opinion that by reason of the size or nature of any secondary standard or working standard, it is not desirable or practicable to put a stamp thereon, it may direct that instead of putting a stamp on such secondary standard or working standard, a certificate may be issued to the effect that such secondary standard or working standard conforms to the standards established by or under the Standards Act and every secondary standard or working standard so certified shall be deemed to have been duly stamped under this Act on the date on which such certificate was issued.
(2) Every certificate referred to in sub-section (1) shall be in such form as may be prescribed and shall contain such details as to enable a clear identification of the weight or measure to which it relates.