100% Australian Merino Wool Designed & knitted in Tasmania, Australia 20.5-micron superwash easy-care Weighing around 200gms a pair makes them substantial socks. Machine washable to 30 degrees C. Wide range of colours. Warm in the cold, cool in the heat, maintain warmth when damp. You can wear these pure wool socks for days, weeks even months (if you need to) and still be polite to the nose, more importantly to other people's noses. Please wash them less, not more... Will our pure wool Mongrel socks live forever, no way! They will wear out; however they can be darned, we know that's disappointing, but it's true. We leave out the often-nasty petro-chemical synthetics commonly used to enhance sock wear time, because of this they won't last forever and nor will they ever be found fouling up our natural environment.