This item was on sale and I bought 3 pairs of these. I normally run about 5 miles every day wearing Adidas Ultraboost 20. First day run was good with these socks on and same with the second run. Guess what! on the 3rd day, this knitted fabric socks started pilling on the back of my foot where arch is. I first didn't really feel it much but just little bit uncomfortable. then it got bigger and I got a blister and the fuzzballs actually damage the shoes where my arch was rubbing against. I paid $180 bucks for my shoes and it is $200 bucks with tax. Now I totally ruined my shoe. I've already filed a complaint about this then amazon only refunded the money I paid for the socks. We'll see what I am going thru later about this matter.