Patent pending ReliaWool Technology in high impact areas provides the longer lasting protection to keep feet comfortable. 1.5" overall height, 1x1 ribbed welt. New 4 Degree Elite Fit System uses two elastics for greater stretch and recovery to keep the sock in place. * 54% Merino Wool, 44% Nylon, 2% Elastane, washer and dryer friendly * Men"s sock sizes - Medium (fits US shoe size 6-8.5) Large (fits US shoe size 9-11.5) X-Large (fits US shoe size 12-14.5). Women"s sock sizes Small (shoe size 4-6.5) Medium (shoe size 7-9.5) Large (shoe size 10-12.5)