@Crow Horse I got around 5 yrs out of mine. I did cut off the rubber cover for a look see and found a strap running between two batteries had rusted into. It has never had water inside it, was always inside my kayak in a yak attack cell block.
I also can’t complain considering what it cost. I did replace it with a Dakota Lithium that was around the same price but with a 10 yr warranty. Ironically I seen a post just this week on FB of a failed Dakota that was taken apart and was rusted pretty good on the inside so I guess time will tell.