The ultimate in foot snugness, Volt Heated Slippers apply 2.2W of warmth to your tootsies courtesy of a 3.7V rechargeable lithium-ion battery. There's even a self-regulating thermostat, while the 100% nylon craftsmanship ensures they're as comfy as they are warm. The design is unisex, so buy two pairs. Trust us, your missus will thank you for it. Plus, it'll stop her from stealing yours.