Solar panel: Used to charge MP3 phones...pads or other controlled devices. Dual USB female ports, easily charge the device through the USB charging cable. You can put the panel in the and use it to directly charge the device. Suitable for outdoor cycling, mountaineering, hiking, camping, traveling, etc.Controller: Integrated industrial microcontroller. PWM load management is completely divided into 4 stages. One-key configuration, digital display, automatic memory function. Double mosfet reverse current protection, low heat generation. Short circuit protection, open circuit protection, reverse protection and overload protection.Solar panel:USB output: 5VNumber of USB ports: doubleSolar panel voltage: DC12-18VSolar panel : 20WController:Model: PWMStep-down charging: 28.8VFloating charge: 27.4VUSB output: 5V / 3ASelf-consumption: less than 10 mADischarge stop: 21.4VVoltage: DC 12V / 24VMaximum solar input: less than 50VCurrent: 10A / 20A / 30A / 40ANominal working current: less than equal 20ADisconnect and reconnect: 25.2 VWorking temperature: -35Celsius-60CelsiusOutput voltage: 12V / 24V automatic identification voltageSuitable for 10V-12V photovoltaic system: 120W solar panel, 12V lead-acid battery, 21V, maximum input voltage.Suitable for 10V-24 V photovoltaic systems: 240 W solar panels, 24 V lead-acid batteries, 42 V maximum input voltage.System connection:1. Connect the battery to the charge controller-plus and minus. If a 12V battery is detected, it will display 1; if a 24V battery is detected, it will display 2. 2. Connect the photovoltaic module to the positive and negative regulators.3. Connect the consumer to the charge controller-plus and minus.colour:As shownMaterial:Polysiliconsize:43.5 x 20CMPackage Contents:1 x 20W solar panel1 x Solar controller (30A)4 x suction cup1 x alligator 1 x car chargerOnly 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.