Smartwool Mountaineering Extra Heavy Crew Socks
Source: bought it new
Proper socks for cold weather activities.
- Lose elasticity in time
They offer good insulation and comfort. In case of very low temperatures, a very thin liner can be used.
They are bulky so make sure they fit in your boots without restricting your blood circulation.
The only complaint is they really get loose after some usage, but that's a natural feature of wool.