QT Bloom Baby Boy Onesie piece Formal Tuxedo Romper with Bow-tie (Black Vest) Machine Wash with Cold Water. Material: Cotton Blends. 3-6 Months: Chest 20" Waist 22" Length 17" 6-12 months: Chest 22" Waist 23" Length 19" 12-18 months: Chest 23" Waist 24" Length 20" 18-24 Months: Chest 24" Waist 25" Length 20.5"