Hotronic Foot Warmer S4 Universal

S SERIES FOOT WARMER Offers up to a combined 30% increase in higher average temperatures and longer durations on a single full charge. Maintains up to 55% of a full charge and 95% of the initial capacity after four years of non-use! Provides power when needed most, in the cold! WHEREVER ONE GOES - WHATEVER ONE DOES Installs in all types of footwear. Transfers from one pair of footwear to another. Use while skiing, snowboarding, bicycling, horseback riding, and during other general cold-temperature activities.