For the most part, this is a very good training underwear. Urine almost does not seep through, so the trousers do not get wet. I had one where the belt came undone. And the plastic underwear that comes with it isn't very protective. This adds another layer of protection. But the urine went through all layers during sleep. This may not always be the case depending on the child or the amount of urine. But they stop leaking better than the Gerber brand, which I also own.