These Heat Holders® women's Millie LITE™ Merino Wool augmented thermal socks have a tog rating of 1.8, making them over 4 times warmer than basic cotton socks. The medium looped pile and soft brushed finish of the inner hold heat and cushion your feet for all-day warmth and comfort. A reinforced heel & toe provide extra protection for heavy use. Fit & Design: Reinforced heel and toe Soft brushed inner 1.8 tog rating