Do you mean the crocheted ones that go inside the diaper? I bought several of these and loved the idea of them because you can wear a fitted diaper without a cover and not get leaks but then I started using Fireflies and they're not lined with microfleece; so, even though the outside of the diaper is not wet, ds skin is. I would use them if I used microfleece lined doublers. I don't use them anymore. I have, I think, three in each size. You don't have to wash them that often if they only have pee on them, just let them dry.
Punkinbutt is the only place I know of that carries them.
HTH,
Jelaine