Section 7 of the FLSA requires that covered, nonexempt employees receive not less than one and one-half times their regular rates of pay for hours worked in excess of the applicable maximum hours standards. However, section 7(o) of the Act provides an element of flexibility to State and local government employers and an element of choice to their employees or the representatives of their employees regarding compensation for statutory overtime hours. The exemption provided by this subsection authorizes a public agency which is a State, a political subdivision of a State, or an interstate governmental agency, to provide compensatory time off (with certain limitations, as provided in § 553.21) in lieu of monetary overtime compensation that would otherwise be required under section 7. Compensatory time received by an employee in lieu of cash must be at the rate of not less than one and one-half hours of compensatory time for each hour of overtime work, just as the monetary rate for overtime is calculated at the rate of not less than one and one-half times the regular rate of pay.