Whether in an expedition hut, a mountainside lodge or just looking to protect your tootsies from the chills at home The North Face Thermoball Traction Mule II Slipper has you got you — and your feet especially — comfortably covered. Snugness and warmth comes courtesy of ThermoBall powered by PrimaLoft insulation, not to mention the water resistant finish and the outsole of 40% recycled rubber which offers a high traction grip.