The uniforms, arms, equipment and supplies necessary for performance of duties shall be those prescribed by applicable federal laws and regulations. Officers shall provide themselves with uniforms and equipment prescribed, and there shall be annually allowed, to aid them in procuring and maintaining the same in condition for service, the sum of $100 each. Such sum shall be paid during the last month of each fiscal year for such year. In the event of service for less than the full fiscal year one twelfth of such sum shall be allowed for each month of service during such year.