Welcome!!!
PUL is a waterproof material that many diaper makers use in pockets and AIOs. Basically it like laminated fabric, does that help????
I use a double stuffed Fuzzi Bunz pocket diaper for nighttime and have yet to have a leak, well, except for a couple of days ago when I changed him in the dark and apparently didn't get "everything" back in the diaper, LOL, but we just pretend that didn't happen
