Hotronic Footwarmer S4 Custom 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! 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.
- 1 Battery Pack (not a pair, just one)
Hotronic Footwarmer S4 battery pack is a replacement for the S4 system, if one of your batteries no longer works. Sold individually.