The socks I knitted for my husband, which he wore with his greens, and which he took in with him for inspection, were wool socks.
Wool. . . the only natural fiber that even when soaking wet will still retains body heat!!
Until I knew this I always ‘gripped’ about the fools that made wool (socks/glove liners/sweaters) part of our lucky bag.
Seems I was the uninformed fool!