What does "Meets UL 458 with marine supplement" mean?

UL458 ensures safety for power converters in stationary and mobile applications and ensures that the unit remains safe for different applications (for example off-grid where there is no permanent safety ground) and even in fault conditions. The marine supplement means that there are some additional tests done to ensure safety for wet environments. Please note that a drip shield is necessary for marine supplement compliance as detailed on page 17 of our manual.  One of the requirements of UL standards is that the testing is done by a 3rd party accredited testing agency which is expensive and time consuming and ensures you are buying a quality and safe product.