Our replacement fan extension harness for the 2017 2019 L5P Duramax allows you to repair a broken or damaged harness without needing to replace the entire fan assembly. This harness is mounted to the fan assembly and connects to the fan and chassis harness. Produced in house, our manufacturing process includes fully automated wire cutting and terminal crimping to ensure you get the highest quality replacement parts you need to get your truck back on the road quickly. Application Notes Fits cooling fan clutch part numbers 15 40577 and 84013368