Every employer employing any employees subject to the Act's minimum wage provisions shall post and keep posted a notice explaining the Act, as prescribed by the Wage and Hour Division, in conspicuous places in every establishment where such employees are employed so as to permit them to observe readily a copy. Any employer of employees to whom section 7 of the Act does not apply because of an exemption of broad application to an establishment may alter or modify the poster with a legible notation to show that the overtime provisions do not apply. For example: