4. Duty of employer to pay equal remuneration to men and women workers for same work or work of a similar nature. - (1) No employer shall pay to any worker, employed by him in an establishment or employment, remuneration, whether payable in cash or in kind, at rates less favourable than those at which remuneration is paid by him to the workers of the opposite sex in such establishment or employment for performing the
same work or work of a similar nature.

(2) No employer shall, for the purpose of complying with the provisions of sub-section (1), reduce the rate of remuneration of any worker.

(3) Where, in an establishment or employment, the rates of remuneration payable before the commencement of this Act for men and women workers for the same work or work of a similar nature are different only on the ground of sex, then the higher (in cases where there are only two rates), or, as the case may be, the highest (in cases where there are only two rates), of such rates shall be the rate at which remuneration shall be payable, on and from such commencement, to such men and women workers:

Provided that nothing in this sub-section shall be deemed to entitle a worker to the revision of the rate of remuneration payable to him or her with reference to the servicerendered by him or her before the commencement of this Act.