These socks have a compressive stitch that helps to increase circulation and reduce swelling and a tighter fit to reduce friction at your pressure points. So hot right now. Made from 90% recycled plastic bottles (RPET) and 10% spandex Compression mesh and rib stitch to promote circulation and reduce swelling Rib transfer at arch for extra support Flat linking seam at toe for comfort To take care of it, machine wash cold and lay flat to dry — we recommend using a microfiber filter or filtering wash bag. ;)