THERM-IC S-Pack 700 B 1pc Sock Battery (T41-0902-002)

Includes 3 manually controllable heat settings via power button; Fitted with Bluetooth technology, you can now control all 10 heat settings via your smartphone, using the Thermic Heat Control App; Keep your feet warm for up to 8 hours; Fits perfectly with all Therm-ic heated socks; Includes a USB charger; Wall charger not supplied