i play. Baby Boys' Classics Ultimate Swim Diaper Trunk UPF 50+ 100% Polyester Imported 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 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