Super Bright LED 9004 Hi/Lo Bulb Conversion Kit9004 Hi Low Beam CREE LED Headlight Conversion Kit HID rely on temperature and requires time to warm up, while these rely on current and light up faster. More efficient than HIDs Uses less energy (25 watts per side) Super Bright! (Brighter than typical HID Kits) HIDs produce UV lights which causes yellowing of the lenses, LEDs do not! Uses fans as heat sinks to help cool! Ballasts are water resistant, uses IP65 Internal Constant Current CPU Gives off