Sold as a set (kit covers both sides). This wiring kit adds the missing wires to your GM door harness for upgrading from small mirrors to towing mirrors. This gets ALL of the lighting features working properly on towing mirrors. This kit is all that is required for 2015.5-2019 trucks. Why spend $200+ on replacing your door harnesses when you can just add the missing wires for a fraction of the price?
This upgrade will work for OEM mirrors (RPO code DQS or DPN) and any aftermarket mirrors that properly wire all of the wires into the OEM style connector.
Link to installation video: https://youtu.be/74yND-l8xwQ