How to Use: 1. Connect the positive and negative poles of the battery to the controller as shown in the figure, and the controller will automatically detect the battery voltage. 2. Connect the positive and negative poles of the load to the controller as shown in the figure. 3. Connect the solar panel to the controller as shown in the figure. Specification: Item Type: Smart Charge Controller Material: ABS Model: GLL1210 Uses: Suitable for home, industry, commerce, etc. Rated Voltage: 12/24V Maximum Photovoltaic Voltage: 50V 10A Solar Panel Power: 130W (12V) 260W (24V) 20A Solar Panel Power: 260W (12V) 520W (24V) 30A Solar Panel Power: 390W (12V) 780W (24V)USB Output: 2 USB outputs, 5V/2.5A (maximum) Package List: 1 x Smart Charge Controller 1 x User Manual Note: The charge controller is only suitable for open type/AGM/gel type acid batteries, not suitable for nickel metal hydride, lithium, lithium ion or other batteries.