This Attwood Trailer Adapter accommodates the connection of a trailer wiring harness from a 7-way to a 5-way connector. This ensures the connection of a trailer wiring harness and power delivery to auxiliary lighting, taillights, and ground left right and stop lighting. Attwood Corporation has been an award-winning leader in engineering, testing, and manufacturing the highest quality marine products for over 100 years. We deliver safe and reliable lighting, fuel systems, water systems, seating & pedestals, swim ladders, custom upholstery, and general marine accessories that are easy to install and meet regulatory compliance.