UL, known as Underwriters Laboratories in abbreviation, established in 1894 Northbrook Illinois, is a global safety consulting and certification company. The goal of UL is to ensure safety of product under operating, furthermore, brings up safety life for users. UL with strong investigation is the safeguard of product to guarantee on product safety.

UL supports products with physically and environmentally safe, to provide safe living and working environment for model application. UL designs various category of testing on product based on inspection of safety and professionalize of science knowledge, to ensure safety of product during model operating.

UPS (Uninterruptable Power Supply) attached with UL mark are the guarantee of model certified by series tests designed by UL. UPS will go through tests including heating test, battery test, force test and any other electronic related tests assures the function of product with strength, stability and reliability.