Truecharge 20+/40+ 20 and 40 amp output Microprocessor controlled, multistage charging Charges up to three battery banks simultaneously Independent settings for AGM, flooded or gel lead-acid batteries Wide voltage range operation (90-135 VAC, 50/60 Hz) Automatic 21-day top-up program Durable and corrosion resistant chassis Optional remote LED panel to indicate battery and charge status Optional battery temperature sensor Protection Features Over-temperature shutdown and overload protection Ignition protected for installation in gas engine compartments (10TB, 20+ and 40+) Transformer isolated for safety and to protect against electrolysis Reverse polarity protection Short-circuit and surge protection .**Photo shown with optional battery temperature sensor.**