This wiring harness is required for upgrading the OEM rain sensor and auto-dimming rearview mirror in the following vehicles: VW Golf 4, VW Bora, VW Passat 3B, VW Passat 3BG, Audi A3 8L. Easy installation in minimal time, this wiring harness connects the two components to the central electronics, the WIWA relay, and ground. Package contents: 1x wiring harness