I have a 2020 Ford F-150 Lariat. there are three outlets on the back of the truck. The two outlets to the left of the license plate are for connectivity to a trailer. I am unfamiliar with the third outlet. Do you happen to know what that outlet is for and what type of connection is necessary? (Apologies for the naive question and that is in advance for your help.)

 

Are you referring to the rubber cover just to the right of the license plate?

This one is the keyed lock for the spare tire. Must remove first to be able to lower down the spare tire winch using the tools in the tire change kit.