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Merino wool socks (blended with nylon for durability) made in Northfield, Vermont, with a lifetime guarantee.

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.

Spinner of natural-fiber yarns in cotton, silk, linen, cashmere and alpaca for knitting and weaving.

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.