This Charging Tray from SeaLife is compatible with their #SL9831 rechargeable lithium-ion battery for their Sea Dragon LED dive lights. It requires the #SL98312 power cord, which is available separately and has a plug for connection to an outlet. The plug has an LED indicator for charging status. Approximate charging time is 170 min. The charging tray is included with the Sea Dragon lights and the Sea Dragon Pro Duo and Maxx Duo Sets and is offered here as a spare or replacement part.