SOLSOL charges your device with a built-in patented solar panel on the brim. Perfect for golf, running, beach and more. Once the sun hits the hat charging will begin. Plug your own cord into the USB outport located on the left side pocket of the hat, and plug in your device. As long as there is sun the hat will charge, even if you aren’t wearing it. Charging will be intermittent once you move out of the sun. Hat itself is 100% cotton with a five panel adjustable snapback. Compatible with Samsung Galaxy, LG, iPhone 5/6/6S (not compatible with iPhone 7/iOS10) iPad, iPod, iWatch, Bluetooth Speakers & headphones, digital camera, Mp3 player, Smartwatch, tablets and other 5V USB gadgets.