Advanced Heating Technology with graphene heating elements for rapid and even heat distribution, providing immediate warmth. Smart Thermostat Control allows easy adjustment and maintenance of desired temperature, ensuring consistent heat without overheating. Portable and Washable design makes it and flexible for easy carrying, while also being hygienic for repeated use. Eco-Friendly and Safe operation through USB connection, utilizing graphene material for energy-efficient use. Ideal for Various Occasions, perfect for cold , outdoor activities, and office environments, keeping your hands warm and comfortable anywhere, anytime. Voltage: 5 This USB hand warmer is designed to provide quick and efficient warmth with its advanced graphene heating technology. The smart thermostat feature allows you to easily set and maintain your preferred temperature, ensuring you stay comfortable without the risk of overheating. Its portable and washable design makes it convenient for everyday use, while the eco-friendly materials safety and durability. Whether you're outdoors in the winter or working in a chilly office, this hand warmer is the perfect solution to keep your hands cozy and warm. Color: Gray Material: Graphene Composite + Polyester Package Contents: 1*USB Smart Thermostat Hand Warmer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.