The three rods attach to the metal plate and provide you with a towel rack near the outdoor shower.
The 12 volt plug is for convenience. If you have something like a portable compressor or light that runs off 12 volt, it is really nice to have an outside source.
What else do you have questions about? This is the place to ask.
IF my dealer would not have taken the rods out, and put them on,,,,I would never had figured that out. I get a kick out of the "towel rack" for the outdoor shower but no place to hang a curtain. I was thinking of making a circle rod to hold a curtain for an outside shower if my kids start coming back too dirty...but it is very low on my list.