AUKEY 21W Solar Charger with SunPower Solar Panels, Stand, 2 USB Ports for Smartphones SunPower Solar Panels with solar conversion efficiency of up to 23.5% Dual USB ports - Up to 2A output each or total 4A max output under direct sunlight - Automatically detect & adapt to your USB powered devices to provide the fastest charging speed Water & Weather Resistent - PET laminated solar panels with high-wear PVC fabric Foldable design for easy transport - great for camping, hiking, picnics, and other outdoor activities Package Contents: AUKEY 21W Solar Panel, User Manual, 24 Month Warranty Card