Baby Gear Baby Boys' Newborn Monsters 3 Pack Rattle Sock Sock: 68% Cotton/24% Polyester/5% Polyamide/3% Elastane; Rattle Content: 100% Polyester Imported Machine Wash Sock = 68 percent cotton, 24 percent polyester, 3 percent elastane, 5 percent polyamide rattle content = 100 percent polyester with 100 percent polyester fiberfill Rattle noise Fits up to 12 months Machine wash cold