Wegreeco Swim Diaper: Size Large is great for baby nine months - three years old, weight 20-40 lbs; Size Small is great for baby 0-8 months, weight 10-19 lbs, if the baby is thin, we suggest size S Cute Prints: Outer layer, designed for holding solids when swim Interior mesh: Soft to your baby and helpful for holding solids or poo Adjustable Swim Diapers: Adjust the swim diaper size by front & waist corresponding snaps. Great for babies from birth up to 3 years old and great help for Mommy Package:3pcs per pack