Lauren Madison Baby-Boys Newborn Infant Three Piece Short Pant Outfit Set 100% Polyester Made in US Dry Clean Only The Shorts and baseball cap have an elastic back for best fit Fabric covered buttons on front of shirt 0-3 Months fits birth to 12 pounds, 6-9 Months fits 12 1/2 to 16 pounds, 9-12 Months fits 16 to 20 pounds button back closure