Charging Type: MPPT. Current: 30A, 50A, 70A (optional). Size: 17.5 14 4cm/6.9 5.5 1.6in(30A), 21 19.2 5.5cm/8.3 7.6 2.2in(50A), 22.8 20 5.5cm/9 7.9 2.2in(70A). Use a 12V battery with a 17 volt solar panel, use a 24V battery with a 34 volt solar panel.
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