Personalized Pi Math Day grunge Baby Bib. Pi Math Symbol Baby Bib - Black has fun grunge look. graphic licensed from and c. www.graphicsfactory.com Our Baby Bib is rated high in convenience and durability and with a variety of fashionable colors, your baby can be trendy. Mix and match to any outfit. 100% cotton ring spun combed heather colors are cotton-poly. Width 7.75", Length 11.75"