More Info
Give us info what year your 380 and more important what type model
and info what type of battery how they install and where on your boat.
My 07 H-36 when new were 2-4D's


yes really heavy hard to move
and they were in a special battery box I think Hunter made and in port side cockpit with FP Gen and my boat listed to port.
After a few years maybe 5 years they needed replace thank goodness I changed to 4-6-volt T-105's and moved to them under my starboard salon seats and be
there since 2011 and no more list.
So you could add what ever batteries fit better.
Nick