Smart Hand Warmer: Built-in 2 temperature sensors with smart chip control, ensure safe use of controlled temperatures. Overcharge, over-discharge and short-circuit protection. Adjustable Temp Mode: Press the switch and instantly release release of heat in seconds. 3 levels of temperatures 104F/40C, 122F/50C,140F/60C at your choice. Portable Power Bank: 10000mAh lithium ion rechargeable battery with Micro USB charging port. It can also be used as a power bank to charge your electronic device in emergency. Warm Winter Gift: It's a MUST HAVE to spend a cold winter, especially for pain relief for heat therapy needs. Gift for Birthday, Mother ; Father's Day, Thanksgiving Day, Christmas. Smart Application: LED flashlight illumination, high frequency vibration for massage. Daily use in winter for the seniors, use in school for your kids. Shockproof, anti-skid, explosion-proof. Size: 110*63*33mm Colour: Black Packing list: 1pcs