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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.

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.

Grupo Inca textile company in Arequipa making alpaca, baby alpaca and vicuña knitwear, coats, woven fabrics and scarves for leading fashion brands.

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.