i play. Baby Girls' Tankini Set with Built-in Reusable Absorbent Swim Diaper 82% Nylon, 18% Other Fibers Machine Wash i play., Inc. is the original swim diaper manufacturer with over 20 years experience making, testing and improving our patented ultimate swim diaper UPF 50+ fabric. Babies have sensitive skin and sensitive eyes, so special care must be taken to ensure they are properly protected from the sun while playing outdoors The i play. ultimate swim diaper provides layered protection. A waterproof layer, absorbent layer and a lightweight wicking layer Secure fit-trim and snug fitting around the legs and waist to contain solid matter No other diaper necessary 82% Nylon/18% lycra fabric