Wide Compatibility This dual function device serves as a hand warmer and a USB power bank, providing outdoors heat and charging for your USB devices. It fits smartphones, tablets, cameras, and more, making it an essential companion for outdoor activities. Adjustable Temperature It has multiple temperature levels to meet different warmth needs. Powerful Battery and Charging A capacity battery offers long lasting warmth and can also be used as a USB power bank to charge devices when there are no available outlets. Portable and Ergonomic Compact and lightweight, this hand warmer is convenient to carry in a bag or pocket. Its ergonomic design fits comfortably in the hand, suitable for hiking, camping, and commuting. Use Scenarios Hiking or trekking in cold weather: keep warm and charge your phone or GPS. Camping trips: relieve the morning chilly air and charge essential devices at the campsite. Daily winter commute or travel: get reliable warmth and power while on the move.