Electric Hand Warmer Rechargeable/ 5200 mAh Portable_Charger (Black)Your Life Saver in Winter-- Rechargeable Hand Warmer Longer Working Time 3 Heat Setting in 1 Button Exquisite Comfort Warm Up Fast Smoothy Surface Safe to Use Hand Warmer Function 1. Long press the switch key over 3s to turn on the mode of hand warming. ( display red light ) 2. Whe..