ProMariner 43021 ProSport 20+ Generation 3 20 Amp, 12/24/36 Volt, 3 Bank Battery Charger The 12/24/36V, 20 Amp, 3 battery bank ProSport 20 Plus waterproof battery charger delivers fast efficient charging in a lightweight design. Not compatible for 4D batteries Distributed on Demand Technology utilizes 100% of the available charging amps and automatically distributes charge amongst all the batteries as needed . The result is faster, more efficient charging Advanced technology eliminates time consuming troubleshooting by clearly indicating system and battery connections are OK or if a fault is present on a specific battery bank During short or long-term storage, ProSport automatically reconditions all batteries on board once a month for maximum battery life and performance Compact and rugged extruded aluminum design, dual in-line DC safety fuses for trolling motor and house battery banks. Built-in over-voltage, overload, over-temperature, reverse polarity and ignition protection