Sock Ons Clever Little Things That Keep Baby Socks On! 3 Pack - White 0 - 6 Months. Sock ons are award-winning garments that keep baby socks on! they are worn over the sock and "lock" them into place with a patent pending design. Sock ons are an ingenious and trendy solution to a very annoying problem and are an item that no baby (or sane parent) can do without!Made of soft, stretchy material. 82% Nylon 18% Elastane. Machine Washable or cold water hand rinse and hang dry.