... design, and elaboratly design unique invisible battery area. It is convenient to do outdoor sports in winter, with simple operation, good warm ... give you unlimited warmth and care in cold.Good warm effectHigh capacity rechargeable Li-polymer battery, Votage: 3.7V/7.4V, Capacity ... 4-10 hours, and maintain the temperature about 38-50cStylish : battery heated gloves,rechargable battery heating glove