Thermic SmartPack RC 1200 with Remote Control Boot Heaters 2016 Suitable for use with all ThermicSoles and boots with ThermicInside Ultralight lithium-ion batteries providing warmth for up to 22 hours: 1: 37C / 99F 16 - 22h 2: 45C / 113F 7 - 10h 3: 70C / 158F 3 - 4h The 3 heat levels can be set at the push of a button: 1: 37C / 99F 2: 45C / 113F 3: 70C / 158F The Impulse Control stimulates the blood circulation Global charger (incl. country specific adapter) with automatic charging function, Extremely short charging time (3-4h)