0-3M Romper Length: 37 Bust: 48 Sleeve: 9 Pants Length: 37 Waist: 36 Advised Age: 0-3 Months. 3-6M Romper Length: 39 Bust: 50 Sleeve: 9.5 Pants Length: 39 Waist: 38 Advised Age: 3-6 Months. 6-12M Romper Length: 41 Bust: 52 Sleeve: 10 Pants Length: 41 Waist: 40 Advised Age: 6-12 Months.