This product consists of harnesses designed to facilitate easy access to your vehicle's headlight or fog light wiring within the housing. With these harnesses, you can extend these connections outside the housing by passing them through the dust cover. The installation process involves drilling a 7/8" hole in the dust cover, threading the wiring through it, and using the provided rubber grommet to create a waterproof seal. These harnesses are compatible with H8, H9, H11, and H16 style bulbs, and they are similar to the wiring found in HID conversion kits. However, they serve a distinct purpose, allowing you to mount CANBUS modules or PWM modules on the exterior of your headlights. This not only simplifies installation but also helps reduce the heat generated by the bulb and module, ensuring efficient and safe operation.