Infant Sizing
The infant size vest fits babies with a head circumference of 15 inches (38 cm) or smaller.
- Girls: Most girls under 3 months old should fit in an infant vest, but between 1 month and 4 months parents should measure their baby's head to make sure. It is possible for a baby girl 6 months old to fit in an infant, but she'd be small for her age.
- Boys: Most boys will out grow the infant vest around 2 months old. While it is possible a small baby boy, who is almost 4 months old, could fit in an infant size vest, parents should measure their boys between 3 weeks and 2.5 months old.
* These age brackets are based on US CDC growth rate charts. Age brackets will vary by country. Please measure your child's head to ensure a correct size.