Personalized Pi Day Math Symbol Celebration Party Infant Romper. Celebrate Pi Day with a Infant Romper - White featuring distressed look math symbol logo for students, engineers or a math teacher. Meet your new favorite outfit! Keep dressing simple with this one piece, lap shoulder t-romper. Super soft and perfect for baby's sensitive skin. 5.5 oz. 100% combed ringspun cotton premium jersey (CVC Colors are 60/40; Heather is 90/10 combed ringspun cotton/polyester)