... for below outdoor Activities in cold weather : 1. 3.7V Lithium Battery operated 2. Lithium Battery rechargeable at 300 cycles3. Far infrared Carbon Fiber Heating ... , waterproof & Windproof.7. 3 temperature settings: Low, Medium, High.8. Available in 4 Unisex Sizes: S, M, L, XL9. Lithium Battery absolutely stable, safe ...