Personalized Physics Heart Dark Products Newborn Layette. Physics text with a large P and a heart dotting the i in physics is a fun gift design for students, teachers and physicists at birthdays, holidays, back to school and graduation. 100% combed ringspun cotton 5.8 ounce 1×1 baby rib sleeper. 3/8" flatlock binding at envelope neck and cuffs. Back sleeve flap to protect hands. Elastic opening at bottom. Infant: 0-3 Months