Beau and Belle Littles Premium Reusuable Swim Diapers are adjustable from about 2 years to 4 years. We are a small family based company from Loveland, CO. The best part about having an adjustable swim diaper: it lasts longer than other sized options one swim diaper instead of 4-6 different sizes. They come off easily with less mess like a regular diaper (no poop down the legs like the pull-up type swim diapers). The swim diaper is constructed using PUL outerlayer fabric which contains the poop. The polyester mesh inner layer is soft and easy to clean. The Nageuret doesn't contain an inner absorbing layer because once you're swimming that layer would absorb the water and weigh your baby's bottom down. You don't have to worry about having excess water in fabric against baby's skin which is the #1 cause for diaper rash in swim diapers. The elastic around the waist and legs is comfortable and doesn't cause chaffing like the tough elastic in other diapers or the scratchy fabric from disposable diapers. You can have confidence that you are keeping the pool poop free by using a Beau and Belle Littles swim diaper. **Please Note swim diapers are not designed to contain urine.**