Bamboo has been grown for millennia in Asia without the use of pesticides. It is rarely attacked by any pests and not susceptible to diseases. The reason for this, Japanese scientists have found, is a unique anti-bacterial agent of bamboo named “bamboo kun”. This substance, combined with the tight molecular structure of bamboo fibres, are believed to give it its anti-bacterial and bacteriostatic properties – which is not diminished even after more than 50 washes! It is also quite different from chemical additives which can often cause skin irritations and other problems.Made from the great "smooth comfort against the skin" material - 75%Bamboo, 20% cotton, 5% elastaine. They are durable and keep their shape throughout many washes.