For those who want the lightest running sock but still want a Super-fine Merino wool, the Ultra-light fits the bill. Nothing but protection between you and your running shoes.
Small Women's 5-7
Medium Men's 6-8 Women's 7.5-9.5
Large Men's 8.5-10 Women's 10-11.5
XL Men's 10.5-12.5
XXL Men's 13-15.5