Just curious what this is and what it does.

Hello all, first time posting here. I was wondering if any pro could tell me what this is and what it does.

It's just screw on to pipe and its wired to a carlin 60200-02fr relay T T screws .

Does anyone know what it is and what it does for I never seen it before.

Thank you for your time with any insight you can give.

Ken C.