This solar battery charge controller automatically manages and regulates the voltage and current going into the battery from the solar panel, and its designed with short-circuit protection, open-circuit protection, reverse polarity protection and over-load protection in order to ensure that the batteries are not overcharged.Features Color: As shown. Size: 6.86x5.34x2.2cm/2.7x2.1x0.9 inch. Material: ABS. Stable performance: Built-in industrial microcontroller for stable operation in cold, high temperature and humid environments. The voltage is automatically recognized and intelligent, providing more convenience for your life. Made of material for long time and durable use. It has a simple design, but very practical in use, bring much convenience to you. Comprehensive protection: Provides overcharge, overdischarge, overload protection, and short circuit and reverse connection protection.Specification Rated current: 20A. Rated voltage: 14-50V. Photovoltaic input power: 300W. Peak power voltage: gt;15.5V. Output to battery voltage: 13.8V. Working temperature: -40~65 C.