Sizing Information - Small: 0-6 Months | Medium: 9 Months -3 Years | Large: 4 Years+ (fits adults too!); Dimensions - Small: <17" head circumference | Medium: 17"-18.75" head circumference | Large: 19"-22.5" head circumference; Medium: 7"L x 7"W x 0.5"H; Stretchable rib knit design to grow with your child; Foldover cuff that can be worn rolled or unrolled; Exclusive to Bloomingdale's; Imported