AutoTechSalon Premium Slimline H4 9003 HB2 100w PnP Ceramic Relay Wiring Harness Bulb Headlight Foglight Booster 12v Typical results yield at least a 1 volt increase to the bulb socket leads, resulting in 30-50% greater output from your stock or aftermarket halogen bulbs. Simple plug and play 30 minute installation...zero messy cutting or splicing. Retain all original vehicle integrity and functionality. NEW Custom snug-fit flexible rubber insulation tubing offers a space saving of over 50% over our previous version's loose-fit ribbed plastic insulation. MUCH greater wire flexibility for tight angles + vastly increased space saving = a far more elegant and streamline installation All ceramic output plugs support aftermarket bulb wattages up to 100w safely and effectively. Includes 3 industrial strength translucent zip ties as a bonus, for a complete 'out of the box' upgrade solution