ProMariner ProTournament 240 Elite Waterproof Battery Charger 24 Amp - 2 Bank The ProMariner ProTournament is the fastest battery charger with the most features in its class. This onboard charger has been specifically designed to deliver maximum charging performance to extend battery life. The ProTournament works to keep you on the water longer with its tournament-winning technology by providing the following 100 charge upon completion of multi-stage charging process, and 100 charging output wit