The Act applies to employees “engaged in commerce or in the production of goods for commerce” without regard to whether such employees, or their employer, are also engaged in other activities which would not bring them within the coverage of the Act. The Act makes no distinction as to the percentage, volume, or amount of activities of either employee or employer which constitute engaging in commerce or in the production of goods for commerce. Sections 6 and 7 refer to “each” and “any” employee so engaged, and section 15(a)(1) prohibits the introduction into the channels of interstate or foreign commerce of “any” goods in the production of which “any” employee was employed in violation of section 6 or section 7. Although employees doing work in connection with mere isolated, sporadic, or occasional shipments in commerce of insubstantial amounts of goods will not be considered covered by virtue of that fact alone, the law is settled that every employee whose engagement in activities in commerce or in the production of goods for commerce, even though small in amount, is regular and recurring, is covered by the Act.[12] This does not, however, necessarily mean that an employee who at some particular time may engage in work which brings him within the coverage of the Act is, by reason of that fact, thereafter indefinitely entitled to its benefits.