Wishbone 25' Trailer Wiring Kit 25' trailer wishbone harness kit wit 4' trunk connector. Wesbar harnesses conform to all applicable SAE, NMMA, and TMA standards to provide years of dependable service. Standard 4-way harnesses have an 18" ground wire except where noted. Wesbar's 5-way plugs mate with all Wesbar 4-way plugs and will operate all DOT required lights. Complete trailer harness kits include all trailer and tow vehicle harnesses, mounting hardware and instructions. 4-Way Flat 25' Trailer End; Wishbone Harness Kit w/ Hardware; 3' Ground w/ 4' Flat Car End; 18" Ground;