(a)the Provident Fund Scheme, establish a Provident Fund where the contributions paid by the employer to the fund shall be ten per cent. of the wages for the time being payable to each of the employees (whether employed by him directly or by or through a contactor), and the employee's contribution shall be equal to the contribution payable by the employer in respect of him and may, if any employee so desires, be an amount exceeding ten per cent. of the wages, subject to the condition that the employer shall not be under an obligation to pay any contribution over and above his contribution payable under this section: