Advanced Heating Technology: Utilizes double-sided graphene heating films for efficient and uniform warmth distribution. Features four adjustable temperature settings: 37°C, 45°C, 55°C, and 65°C, catering to different warmth needs Durable and Comfortable Materials: The exterior is crafted from high-density down cloth fabric that stores heat effectively, while the interior is lined with lightweight fiber cotton filling, ensuring warmth retention and comfort Versatile Power Options: Equipped with a USB connector, this hand warmer can be powered using a power bank, computer, or any standard USB socket, offering heating convenience anywhere (Note: Power bank not included) Portable Design: With dimensions of 40 x 24 x 2cm when unfolded and 24 x 20 x 2cm when folded, it's designed for easy transportation and storage, making it ideal for outdoor activities and cold weather use Reliable Use: Ideal for keeping hands warm during winter without the worry of overheating, this hand warmer provides a dependable way to stay comfortable in cold conditions Specification:? Heating method: graphene heating? Heating temperature: 37℃/45℃/55℃/65℃? Input voltage: 5V1A?? Rated power: 9.5W?? Plug interface: USB? Unfolded size: 40 x 24 x 2cm? Folded size: 24 x 20 x 2cm? Note: The product does not include the Power Bank and USB extension cablethe pictures are only for the renderings.