What is HID? HID (High Intensity Discharge) refers to lighting technology that relies on an electrical charge to ignite xenon gas contained in a sealed bulb. A normal halogen bulb uses a filament which can burn out in as little as 200 hours. HID bulbs are gas filled capsules that are rated for a lifespan of nearly 4500 hours. Also it shines much brighter due to this technology. Our Ballasts: 1.Voltage from 9~16V Applicable for most 2.SMR super microelectronic memorial chip Super capacity, can digitally parse and memorize different voltage and unstable electric current information, which will bring a guaranteed performance and life-span of HID lamp 3.Pure aluminum casting insulative and never desquamates 4.Constant temperature protection Working temperature will not go up with longer lighting time. Even after2~8hours of lighting, it can still keep under 75°C,which complies with the international standard. Attention: Please be noted that it can not be used with BMW, Mercedes-Benz, Audi, Lamborghini and all the other Sports Cars and Luxury Cars. Package include: 2 x Xenon Bulbs 2 x Ballasts All necessary wires and install accessories