Supposedly a life time assurance, but for the money if we receive a year or two out of these we might be happy. So far, we like them much better than merino as our feet feel to stay drier. They usually seem to be holding up well. PaPa K mentioned: https://generateurdevbucksswitchq41594.hazeronwiki.com/7531020/5_essential_elements_for_rhythmic_gymnastics_socks