Compliance with the US safety regulations is evidenced by a certification mark of a certified test laboratory (Underwriters Laboratory). For the certification of his products, the manufacturer has to prove that they comply with the specified safety requirements.
The field attachable connector versions of the M8x1 and M12x1 series are now UL-approved in accordance with UL 2238. In addition to the standard products with A coding (M8x1 and M12x1), the B and D coded variants (M12x1), axial or angled with the corresponding rated voltage and current rating values, are also certified.