Sierra International TC43624 4-Pole Polarized Round Connector Set Sierra TC43624 4-pole Polarized, Round connector set; (1) trailer side, (1) tow vehicle side, (2) soft pliable rubber caps Before ordering, please verify this is the correct part for your application. For assistance, please call sierra's Tech support at 1-877-663-8396 All sierra Parts qualify for and are covered under sierra's industry leading customer satisfaction warranty