§4174. Marking of approved weights and measures.

It shall be unlawful to manufacture, offer or expose for sale or sell or give away for use in trade or commerce or to use in trade or commerce any weight or measure or weighing or measuring device unless it shall be conspicuously, clearly and permanently marked for purposes of identification with the name, initials or trademark of the manufacturer, and with the manufacturer's designation, which positively identifies the pattern or the design of the device and in such manner as may be prescribed by rules and regulations authorized by this subchapter, provided, however, that, whenever it shall appear to the satisfaction of the bureau that any type of weight or measure or weighing or measuring device is such as to render it impracticable to mark it as required by this section, the bureau shall furnish a certificate to that effect to any manufacturer applying for the same, and such weights and measures and weighing and measuring devices need not be marked as required by the provisions of this section.