What the heck is this:



And what is it for?

Thanks.

 

It's a voltage regulator.

 

I see your regulator that controls the overflow from the charging system,

 

Its basically a fancy switch that turns the alternator output off and on to keep the output voltage around 14 volts so you don't blow up batteries, lights, accessories, etc.

 

The fin's are there because the current flow makes it hot, those are heat sinks/vanes,, keep the thing clean

 

Short description: voltage regulator.

Longer description: This device turns the ~36volt, 3-phase AC voltage from your alternator, into nice, even 12-14 volts DC to run all your electricals and charge your battery. It does get hot in that transformation process, and is why it has cooling fins.

It's also unplugged