It's hard to get excited about putting your feet into a pair of stiff ski boots when it's well below zero outside, and even if you do muster up the willpower to weather the cold, chances are you'll be done after just a few runs. Well, your days of letting bone chilling temperatures ruin your time spent on the mountain are numbered, because the Lenz Set of 3. 0 Heat Socks and 700 Lithium Packs are here to keep your feet warm and comfortable during the coldest days you encounter. This pack comes with a pair of Lenz heat socks, which are made with a moisture wicking and breathable blend of nylon and merino wool. The socks are fitted with an integrated heating element that heats the toes and balls of the foot. The kit also includes two lithium packs that attach to the top cuff of the sock and provide up to four hours of heat. Lens also threw in an USB charger, so you can keep the battery packs charged and ready to go.