ALEKO SP20W24VSC202 24V 20-Watt Monocrystalline Solar Panel SC202 Charging Controller Kit Battery over-charge protection, Battery discharging protection Operating Voltage (Vmp): 36V. Open Circuit Voltage (Voc): 43.8V Operating Current (Imp): 1.14A. Diode type: By-pass 1*3A. Dimensions: 19 x 13.7 x 1 inches LED 1 shows when battery is fully charged. LED 2 shows when the battery is over-charged