[What is this under dash harness?]

It's not near me. I just got the photo and was hoping to get some insight from those of you out there who have spent time working on these trucks. I did notice that toggle switch and maybe it's part of the system as well. I'm sure my Son's girlfriend has no idea what it is as this is the way she received it.

 

I appreciate your feedback.

[What is this under dash harness?]

This is on an '88 Pathfinder SE with 5spd trans. I don't know if this is factory or aftermarket. Perhaps somebody out there has seen this before.