FUNNY AIRSPEED VELOCITY OF AN UNLADEN SWALLOW T-SHIRT Maths Solid colors: 100% Cotton; Heather Grey: 90% Cotton, 10% Polyester; All Other Heathers: 50% Cotton, 50% Polyester Imported Machine wash cold with like colors, dry low heat Perfect for Birthdays and Valentine's Day. Or Graduation and back to school present. Even for Christmas, Black Friday, thanksgiving or Halloween. Know a sister brother father daughter or mother that needs this? From the brand that brought you "avoid negativity" and other great maths student or teacher and geek humor tees. FUNNY AIRSPEED VELOCITY OF AN UNLADEN SWALLOW T-SHIRT Maths Lightweight, Classic fit, Double-needle sleeve and bottom hem