This Solar Battery Charge Controller automatically manages and regulates the voltage and current going into the battery from the solar panel, and it can ensure that the are not overcharged. Features - - Size: 13.35x7x3.5cm - Material: ABS - Made of material for lasting use. - Dual USB port, convenient to use. - LCD display for easy controlling charge and discharge. - Suitable for charging lead- battery (12V / 24V battery automatic identification, B1), lithium ion battery (B2), lithium iron phosphate battery (B3). - Note: can only used with photovoltaic panel, please install it on flat and ventilated surface. Specification - Rated charging current: 20A. - Rated discharging current: 10A. - Working voltage: 12V/24V. - Charge cut-off Voltage: 14.4V(B1) 12.6V(B2) 14.6V(B3) - Discharge cut-off voltage: 10.7V(B1) 9V(B2) 10V(B3) - Discharge recovery voltage : 12.6V(B1) 10.5V(B2) 12V(B3) - USB output: 5V 2.5A - Working temperature: -35 ~ 60&deg;C. - Standby current : <10mA Package list: 1 controller