The O.N.E diaper is truly a one-of-a-kind all-in-one cloth diaper. All of its exclusive benefits are even listed right in its name, as O.N.E. stands for: Outlast closure, No prep, and Easy to use, making it easy to remember why the O.N.E. diaper is (or will become) your No. 1 all-in-one cloth diaper.