For trucks with an aluminum body, galvanic corrosion can become a problem when installing vehicle-to-trailer wiring without the appropriate protection. This isolator kit allows you to install an original equipment extension or custom wiring harness extension in an aluminum truck bed without having to worry about ruining the truck's finish. It includes four bolts for secure mounting and four plastic well nuts to isolate the fasteners from all aluminum surfaces. This kit is compatible with a variety of CURT 7-way RV blade harnesses, including #56000, #56001, #56070, #56071, #56080, #57008 and #57010.