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Mount Airy, North Carolina wool sock mill that knits merino socks for private-label clients such as REI and L.L.Bean, makes licensed lines, and owns Farm to Feet; some programs use synthetic yarns.

Swiss shirting-fabric maker using extra-long-staple Supima and Sea Island cotton, plus cashmere and linen blends, woven at partner mills.

Norwegian wool brand making merino wool base layers, thermal underwear, fleece-wool layers and beanies, using New Zealand merino knitted in its own Estonian facility.

Sock maker near Braga, Portugal, producing about 3.5 million pairs a year in organic cotton and merino for department stores, chains and brands such as Asket.