Can let low voltage rise to high voltage to activate xenon in bulbs to achieve high brightness lighting Constant power output, energy-saving, protects the HID bulb from damage and provides long lifespan(>5000hrs) Fit for HID series: H1, H3, H4, H7, H8, H9, H10, H11, H13, 9005, 9006, 9007, etc. With waterproof performance, and when short circuit, it will automatically stop working Plug & play, easy to install and no modification required; Applicable to cars, motorcycles, electric vehicles