“AiO” stands for “All-in-One” and means the pad has all the absorbency and waterproofing (PUL) materials sewn in, and is simply placed into your underpants as-is, like you would use a disposable pad.

“L” means Light absorbency, “R” means regular absorbency and “H” means heavy absorbency. “w” Means it contains PUL waterproofing
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