Whatever the qualities of the fabric, this is a disappointing product, especially from a company of Knox's standing. Like it seems to have happened to another reviewer, the bond on one of the sleeves of my garment also failed. I also bought a similar top for my girlfriend, and on that one, the bond failed all around the bottom hem. In both cases, this happened while wearing them, not during a wash. The tops were only washed by hand, in cold to lukewarm water. The "bonded seams" appear to be just double-sided sticky tape, not much different from what anyone can get from ebay. It's a bad idea, poorly executed from Knox.