Swiftwick SUSTAIN FOUR Socks 54% Nylon / 32% Repreve / 10% Olefin / 4% Spandex Made in US Recycled Content Medium Footbed Cushion | Medium Compression | 3 Point Arch Support REPREVE (post-industrial recycled nylon) | Olefin | 200 Needle Construction Managed Compression | Blister-Free | Moisture Wicking | Antimicrobial No Dyes | Chemical-Free Wicking Made in the USA