What's that little box??

[shields]

I noticed a little box attached to the bigger Fuse box, on the inside of the driver side fender. It is like 2 inches long and has a screw in the middle of it with a clear plastic cover. Two wires run out of the bottom and go into the fuse box.

Two circuits are inside with a removable connection between the circuits. I noticed only one connection in my vehicle and the one closest to the driver is missing.

What is this box and what are these circuits. What are these?

[rs4pro3]

it's an aux fuse box, so you can wire up other items. One circuit is a switched 12 volt soruce, and the other is a constant 12 volt source.