SK Hat shop Cool Light Weight Knit Sequins Shimmer Sparkle Shiny Beret Dance Cap Hat Fabrication: 100% Polyester Size: One size for teens and ladies w/ elastic back, S/M Head measurement: 55cm, 21-5/8", Size 6-7/8 to 57cm, 22-3/8", Size 7-1/8 Flat measurement: 10-1/2" x 10-1/2", opening 4" across will stretch.