These classic work socks are durable and universal! Small fits sizes 3-5 1/2 for men, and 4-6 1/2 for women. Medium fits sizes 6-8.5 in men's, and 7-9.5 in women's. Large fits sizes 9-11.5 in men's, and 10-12.5 in women's. X-Large fits sizes 12-14 1/2 in men's. There are 2 pairs of socks per pack, and each pack comes with instructions on how to make sock monkeys!