Spongebob Squarepants Official Childrens/Kids Slipper Socks (1 Pair) 100% Nylon Kids slipper socks with floor grippers and official Spongebob Squarepants designs. Choice of 6 designs. Choice of 3 sizes. 76% Cotton, 13% Nylon, 10% Polyester, 1% Elastane. Machine washable.