Personalized Math Rocks Men's V-Neck T-Shirt. Math rocks with three happy rocks dancing with numbers is a humorous design for mathematicians, students and teachers at birthdays, holidays, back to school and graduation. 4.7 oz., 100% pre-shrunk cotton Narrow, set-in 1x1 mitered V-neck collar Shoulder-to-shoulder taping Double-needle stitched sleeves and bottom hem