Sealed leisure batteries provide great portable power solutions for many uses such as caravans, motorhomes, sail boats and many others The POWERBATT DC31  is  completely sealed from the factory and features the following : - Calcium Technology - Labyrinth Lid - Dual Terminals - Auto and Threaded Post - Strong Ergonomic Carry Handles - Built in Ceramic Filter / Flame Arrestor - High Strength Corrosion Resistant Plates Great for both cyclic and starter applications.