Features: Build-in industrial micro controller, convenient to use. Large LCD screen display with 5V USB charging function. Complete PWM charge management, practical to use. Dual MOS reverse current protection ,low heat production. Build-in overcurrent/short-circuit protection, open-circuit protection, reverse protection, over-load protection. Specification: Condition: 100% Brand New Material: Plastic Type: 10A, 20A, 30A (optional) Size: Approx. 12.4*6.4*3.2 cm / 4.9*2.5*1.3 in Weight: Approx. 192g / 6.8 oz Package list: 1 * Solar Controller 1 * User Manual System Connection: 1. Connect the battery to the charge regulator - plus and minus. 2. Connect the photovoltaic module to the regulator - plus and minus. 3. Connect the consumer to the charge regulator - plus and minus. The reverse order applies when deinstalling! Safety Instruction: 1. This controller is automatically adapted to 12V/24V. When installing for the first time, please make sure that the battery has enough voltage so that the controller can recognize the correct battery type. 2. Install the controller as close as possible to the battery. The battery cable should be as short as possible to minimize the loss and avoid the voltage drop caused by the long wire, which will affect the normal voltage judgment. 3. This controller is only suitable for all kinds of lead-acid batteries (including suitable for OPEN/AGM/GEL). Do not use them on other batteries (including lithium batteries, nickel-metal hydride batteries, etc.) 4. This controller can only use photovoltaic panels as the charging source. Do not use DC or other power sources as the charging source. 5. The controller will heat up when it is running. Please pay attention to install the controller on a flat and well-ventilated surface.