The LED hats are made of 100% cotton, they are soft and breathable. It is very easy to turn it on and off. The LED screen is Detachable. To pair the cap with your smartphone you need to follow the following steps. First step: turn on your bluetooth of the phone, scan QR code by your mobile phone. Second step: download magic display, click APP. Last step: Click connection button, and click refresh button , click the arrow of the options with bluetooth, mobile phone will successfully connecting with your hat soon