DetailsLasting Size Chart A medium weight hiking sock made of sustainably sourced Australian merino wool. It provides excellent thermal insulation and has moisture removing properties. The sock section around the ankle is knitted from a smooth single-layer fabric and the bottom is made of a double layer smooth knit. Elastic around the instep ensures a perfect fit at the bottom of the foot and improves performance during sport activities. The siltex material is also anti-microbial. Material: 75% merino wool, 10% siltex- polypropylene, 10% polyamide 5% lycra – elastane.