Having heated socks is a game changer when battling the coldest conditions. The Therm-ic Fusion Uni S-700B Sock Set is over-the-calf heated socks for skiing and snowboarding in deep winter conditions. The socks include two S-PACK 700B batteries to keep us covered in warmth for up to seven hours, and the batteries can be controlled via Bluetooth on our smartphone so we can customize our warmth.