Based on Battery Packs in ambient temperatures -22°C to -15°C (-9 to +4°F). Based on Heating Element in ambient temperatures 20°C to 26°C (68° to 79°F).
** Setting 2 is the most common setting.
Note: If you are purchasing the the Hotronic Battery Pack Power Plus "S" series batteries (S4 / S3) to replace a Hotronic Battery Pack Power Plus "e" or "m" series batteries, we recommend replacing both batteries. The "S" series batteries are warmer than the "e" and "m" series batteries on the same settings.