Solar system description: Solar panel (receives solar energy to charge the battery) + solar controller (controls the charging and discharging of the battery) + battery (energy storage) (the battery is provided by the customer Details: Solar controller is 30A 12V/24V voltage automatic recognition universal model Maximum power (pmax): 20W color: Black Material: polycrystalline silicon Open circuit voltage (voc): 20V Maximum power voltage (vmpp): 18v Short circuit current (): 1.1A Maximum power current (impp): 0.9A Output: USB 5V DC5521 18V Standard test conditions AM=1.5 Irradiance=1000W/㎡ Temperature = 25℃ [Good material] 1, the is made of plastic and the backplane is made of iron material, which is reusable and durable to use. 2, it has 2 USB outputs, 5V/2.5A. [Superior performance] 1. High efficiency monocrystalline solar cells provide good performance even in low light conditions. 2, and internal diodes prevent night leakage. [Portable Use] 1, if you are taking an extended camping trip or if you are traveling somewhere with an unreliable power grid, this solar panel is a good choice. [Widely Used] 1, this solar panel is suitable for motorhomes, boats, sailboats, yachts, trucks, cars, coaches, passenger cabins, campers, tents, trailers, golf carts, or any other curved surface with irregular surfaces. Tips: The product may be updated constantly, The Actual Product May Have Slight Differences Or Color Differences the color and appearance may be changed, please don't mind. And take a consideration before place the order if you have request for color or appearance. Package Contents: 1 x car battery solar panel system kit Only the above package content, other products are not included. Note: Light reflection 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.