Solar Charger Controller    "10A:   if your battery is 12V ,the max solar panel input is 25V  120W   if your battery is 24V ,the max solar panel input is 50V  240W   20A:   if your battery is 12V, the max solar panel input is 25V   240W   if your battery is 24V, the max solar panel input is 50V   480W   30A   if your battery is 12V ,the max solar panel input is 25V   360W   if your battery is 24V ,the max solar panel input is 50V   720W   If you though 30A is too small, you can buy 60A, one is with wifi function, another is without.   Features:   1.Build-in industrial micro controller.   2.Big LCD display,all adjustable parameter.   3.Fully 4-stage PWM charge management.   4.Build-in short-circuit protection,open-circuit protection,reverse protection,over-load protection.   5.Dual mosfet Reverse current protection ,low heat production."