Build-in industrial -controller. Big LCD display,all adjustable parameter. Fully 4-stage PWM charge management. Build-in short-circuit protection,open-circuit protection,reverse protection,over-load protection. Dual mosfet Reverse current protection ,low heat production. Material: ABS colour: black + green Rated working voltage: 12V / 24V Rated working current: 30A USB output voltage: 5V DC output voltage: 12V Solar panel voltage: Less than equal 50V Float charge voltage: 13.7V / 27.4V Undervoltage protection: 10.5V / 21V Undervoltage recovery: 12.2V / 24.4V Features: No-load loss Less than equal 10mA Circuit step-down: Less than equal 170mV Temperature compensation: -4mV / Cell / Celsius ; Working environment: working temperature -20 Celsius ~ +60 Celsius Storage temperature: -30 Celsius ~ +70 Celsius Temperature requirement: Less than equal 90% No condensation: Installation hole wire number: Less than equal 7 # AWG (16mm2) / Greater than 3 # AWG (25mm2) Package Contents: 2 x Solar Charge Controller Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.