This is the boot-height version of the Trail Runner II, perfect for lightweight hiking or aggressive walking. Medium weight cushioning on the foot and toes provides protection in high-friction areas, while a thin flat knit instep provides a sleeker fit and extra breathability. Features an elasticized arch brace to help keep sock in place and add arch support. Crew height. QCActive.com (Active Endeavors) is your online source for Smartwool and Smartwool Hiking Socks. Smartwool Hiking Light Crew This is the boot height version of the Trail Runner II perfect for lightweight hiking or aggressive walking Medium weight cushioning on the foot and toes provides protection in high friction areas while a thin flat knit instep provides a sleeker fit and extra breathability Features an elasticized arch brace to help keep sock in place and add arch support Crew height Smartwool,Smartwool Hiking Socks,QCActive,Active Endeavors