Personalized Pi Math Day grunge Toddler Full Zip Hooded Jacket. Pi Math Symbol Toddler Full Zip Hooded Jacket - Black has fun grunge look. graphic licensed from and c. www.graphicsfactory.com 7.5 oz., 60/40 cotton/polyester. Jersey-lined double-needle hemmed hood. Pouch pockets for all their treasures. Coverstitched shoulders and armholes. Coverstitched rib waistband and cuffs.