Product description Material: monocrystalline silicon solar panel + PVC Size: folded, 29017030mm; unfolded, 70029016mm Colour: Black Quantity: 1 piece Power: 21 watts Output interface: dual USB Output current: 3500mA (peak current) Conversion efficiency: ≥19% Output voltage: 5V+0.2V Package Contents: 1*Solar Charging Board 1.【High Energy Conversion】:Uses the high-density monocrystalline silicon solar panels convert up to 29%.Tap into the sun’s radiance and power your devices anywhere,Easily capture every ray of sunshine for you.If you have more than one of the same product, you can connect the DC interface with the donated DC cable to superimpose the output power in series. 2.【Extensive compatibility】:The extensive compatibility enables it to charge most electronic products, in the sun for mobile phone/tablet PC/laptop/mobile power supply /PSP/MP4/GPS/ Bluetooth headsets and other electronic devices.Our USB ports and DC port, It can also charge car batteries and accumulators,plus