Product features: this product is a utility model hand warmer (electric hot water bag) made of high-grade velvet fabric and plastic materials, a high energy storage heating liquid is heating body through the semiconductor in the bag evenly heat storage energy, with unique automatic temperature control function, comfortable and soft, safe and reliable, is the new generation ideal fashion of heating quality.      Charging for 8 to 12 minutes can keep warm for 2 to 10 hours.