Heat Holders Original

Warmest sleep sock

Our take On bitter cold nights, this pair of high-loft socks kept our feet warm. “I usually have to wear multiple pairs of socks to bed, but used only this one on single-digit nights in Banff National Park, Alberta, and never woke up cold,” our gear editor says. A thick, high-loft synthetic yarn traps warmth and provides a slipper-like feel, and creates an interior that’s even more plush than other socks of this type (surprisingly so, given the majority-acrylic material). Ding: The yarn begins to lose loft after about five washes; although our tester didn’t notice a major drop in warmth, he missed the feel of the new, fuzzier yarn.

Trail cred “This sock breathes well for its warmth,” our gear editor says. “My feet didn’t get too sweaty while I was digging out my tent in glaring sunshine on Banff’s Freshfield Icefield in 25°F temps.”

One size each m’s and w’s