Storage Battery Systems Inc. backs the VRPPP Series battery with a 20 year waranty, the first 5 of which are at 100%with the balance of 15 being pro-rated. The valve regulated vents are low pressure & flame arresting. Polypropylene cases with fusion welded covers are flame-retardant. The VRPP has an extremely high cycle life of 2000 events to 20% DOD. The internal plate hardware is nickle coated for better conductivity & corrosion resistance. When the VRPP cells are properly floated at 1.42vpc, there should be no need to add water for up to 20 years. The patented Polypro fibrous separator contributes to the 85%-95% recombination efficiency. In the unlikely event that levels do become low, there is a provision to make adding water possible. This characteristic makes the VRPP ideal for remote locations where frequent inspections are not easily accomplished or where duty cycles, temperature & discharge rates would cause high water consumption in other designs.