Hella offers wiring harnesses for their kits as well as universal wiring harnesses.   

Hella makes specific harnesses for, amongst others, the Rallye 4000 Luminator Series (Halogen), Xenon HID Headlamps, BiXenon HID Headlamps, Xenon HID Auxiliary Lamps, the FF100, FF200 and FF300 Series and Micro DE.  

You get the quality you expect form Hella Wiring Harnesses. Hella Wiring Harnesses include wiring, connectors, relay, fuse, and switch.