These batteries are smaller in size than normal large deep cycle batteries you may use to power a boat cabin or a camper for an evening. Because of the AGM and VRLA (valve-regulated) technology, which avoids spills and overpressure, these batteries are rechargeable, maintenance-free, and spill-proof. It is a sealed 12-volt 75-ah lead acid battery. Due to the shipping procedure, there are times when it may come to you with visual flaws. PROS🟢 AGM and VRLA valve regulated technology Long life for deep discharge usage CONS🔴 Some users indicate unstable functioning