This zipper opens from bottom to top. When mom changes diapers, baby’s body is still covered without completely opening the zipper. Super soft, breathable and stretchy bamboo rayon fabric is good for sensitive skin. Snug-fitting to comply with the CPSIA regulations. The ankles are elasticated for a perfect snug fit. Chin protector on top of zipper head to prevent rubbing. Anti-slip grips at the bottom of feet for size 12-18M & 18-24M.