Maintenance-free calcium battery sealed type.Accessories: Battery body, battery case, warranty card, battery connection terminal.Please use it for fishing, outdoors, hobbies, disaster power supply, and 12VDC electric products.Exclusive shoulder bag included.Because it is maintenance-free, there is no need to manage the electrolyte inside.Because the sealed case is used, it is much safer that the electrolyte does not come into direct contact with clothes or body.Large capacity 28AH provides ample power even when connected to high power consumption electric products.