The puffy vest is essentially the ideal layer for winter, providing just enough warmth to keep you comfortable without overheating. Ecaolf's St. Moritz vest might be our favorite sleeveless coat on the market. Each vest is made using recycled PET polyester from 60 plastic bottles, diverted from the landfill and onto your body. Super soft, with an insulated down filling and handy concealed pockets, the St. Moritz vest delivers more of what we've come to expect from the Spanish sustainable fashion brand. It is available in six colors, ranging from the flashy (mustard yellow, Yves Klein blue) to the more subdued (deep navy, khaki green).