I have four 6V batteries in my 5th wheel for now. I just changed them all out last spring and went with polar batteries not sure who makes them but I get a discount because of where I work and I have been impressed with the car batteries I have been purchased from them. My main concern was price this time around and at least being a deicent quality. my last batteries lasted me 14 years but I am planing to sqitch over to LiFePO4 in the next couple years on the 5th as it is working real nice for the camper.