Inserts and doublers can be made out of a variety of materials. Pocket diapers are designed with a stay-dry layer of fleece, Minky, microsuede, or other fabric that wicks moisture away from the baby. Because of this barrier, microfiber is a fairly common pocket diaper insert. You shouldn't place microfiber right next to your baby's skin (such as in AIOs and AI2s), since it can cause dryness and irritation.
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