I have purchased over 40 pairs of Kentwool socks over the past 15 years. I have tried others, and none are better--in fit, comfort or durability. I walk over five miles daily, and play golf three times a week, always in Kentwool socks. In this particular order of fouridentical pairs, one pair had a slight defect in the ankle elastic. I contacted Kentwool, they immediately sent me a free mailing sticker, I shipped the pair back and they have shipped me a new pair. Excellent customer service.