What are these 3 electrical sockets under my LC100 ?

[ceejay LC100]

Hi all,

I have been looking at installing an aftermarket trailer harness to my cruiser as I think it does not have one factory installed and I need one for my boat trailer.

When looking under the vehicle at the rear, I see 3 different sockets. One is on the right side near the exhaust hanger and has a cover to it which can be removed.

There is another small socket in the same area.

There is a socket on the left side with blades.

Can someone please explain what each of these 3 sockets are ? Plea see attached photos

 

[Actualeyes]

You can always test the contacts and see if any of them are related to indicators, tail lights, brake lights etc.

 

[ceejay LC100]

yeah I could but that would only show which is the trailer socket. It wouldn't be easy to determine what the other 2 sockets are that way and it would be way easier if some one who knows what the sockets are could post it on here so my self others would know too.