OPT7 2pc Bolt AC 55w Replacement HID Power Ballast for Xenon Conversion Kits THE BRIGHTEST: 20-30% brighter light (3900 Lumens) than the standard Bolt Series ballast. THE SMARTEST: AC Digital Logic technology keeps your lights clear and prevents flickering by adapting to the voltage of your vehicle. THE TOUGHEST: 100% Weatherproof Stainless Steel casing, Grade 7 silicone sealant, and an AC Digital chipset ensures your unit will last for years to come. THE EASIEST: QuickSnap power connectors allow for easy plug-n-play installation.