Some of these socks are RWS-certified. The Responsible Wool Standard (RWS) is a set of audited protocols establishing high levels of sheep and land management practices, promoting healthy ecosystems, biodiversity, and animal and worker welfare. 100% of the wool in RWS-certified socks has complete traceability through each step of the supply chain from the ranches and sheep where it grows to the retailers where it is sold. Our RWS-certified products use wool grown by the Shaniko Wool Company and RWS-certified family-owned ranches in the Western United States. The DeFeet Woolie Boolie is our cushiest sock, with a cult following for all the right reasons: woolie warmth, padded comfort, and durability.