*USB CHARGING DESIGN: From 95F to 122F and 4 classes timing from 10 to 30 minutes.Powered by PC, power bank, USB adapter. Heating temperature and time can be adjusted by controller, base on your requirement. 45-50C under 20mins can make your eye feel the best. *MAIN FUNCTION: Stimulate the blood circulation & relax the regional muscle to eliminate the inflammation swelling,keep warm, massage muscle, relieve fatigue, improve blood circulation, eye cover sleeping mask for woman & men,Say goodbye to eye bag, black eye. *REMOVABLE AND WASHABLE: Compared with disposable hot steam eye mask, This heating eye mask is reusable and environment friendly. Cover is made of 100% cotton, comfortable, removable and washable. Really a heathy and helpful eye protector. *ERGONOMICS DESIGN: Ergonomics design eye mask well conforms to the face and fits over the eyes. Heating eye mask fits all head sizes with an adjustable pain-free head strap. *HEALTHY & CONFORTABLE: Heating eye mask a good choice for you go into deep sleep at home, take a rest for eyes at office, enjoy yourself on travel and have in the hotel,dissolve away the day's stress, give eyes a super Spa.