The BabyBjorn One Carrier Bib will protect the upper part of the carrier when baby dribbles and chews on it. This Usually occurs when your baby is in outward facing position. Using the BabyBjorn One Carrier Bib on the carrier means that you wont have to wash the carrier as often. Just wash the bib. Baby will also enjoy chewing on the bib so its good to know that there are no harmful substances.