This men's and women's REI Co-op Vest is one of our favorite vests we've tested since it's warm, but thin, and easily layers underneath a jacket. A pair of high-quality ski socks that don’t ...

It features 750 fill power duck down and is rated TEI 3 according to the brand's own Thermal Experience Index. This means it's capable of keeping you warm from roughly 14° Fahrenheit down to -4°.