Teko SIN3RGI Midweight Merino Wool Poly Blend Casual Walking and Hiking Socks 32% M3Rino.Xc, 33% Evapor8, 33% Nylon, 2% Elastic Made in the USA and Imported Dries fast and is 40% more durable than pure merino SIN3RGI is a blend made from Teko's M3RINO.XC merino wool and polyester manufactured from 100% recycled materials