This adapter is designed to prevent electrical accessories from interfering with the electrical system on late model BMW, and other European motorcycles with a Can-BUS electrical system and a City Light 194 marker bulb in the headlight. It includes built-in reverse polarity protection. This item is designed solely to provide a hot trigger wire to activate a relay to power other accessories, such as driving lights, accessory fuse blocks, GPS, or other 12-volt electrical devices when the motorcycle is turned on without upsetting the motorcycle's sensitive CAN-BUS system. This adaptor is also removable without leaving holes in the insulation of the original wiring harness, so it keeps your warranty in place even at the strictest dealers. Installation is simple: 1. Remove the socket from the headlight housing. 2. Unplug the bulb from the socket. 3. Plug the circuit board into the socket from where you just removed the bulb. 4. Place heat shrink over the socket and circuit board and apply heat. 5. Plug the bulb into the new socket. 6. Using the lead coming from the socket, activate an external relay. External relay not included. We recommend the DENALI Power Hub2 (DENELC.0030000) Auxiliary Motorcycle Fuse Block (sold separately) for attaching up to 6 switched accessories to your motorcycle. The following bikes are confirmed to use Canbus electrical systems: BMW F650GS, '08- F800GS, '08- F800S* F800ST* HP2 Enduro HP2 Megamoto HP2 Sport K1200R K1200R Sport K1200S K1200GT, -'05 R1200GS R1200GS Adventure R1200R R1200RT R1200S R1200ST ...and most other R and K series bikes 2005 and later. Please check your motorcycle uses the CAN-BUS system before ordering this part.