Personalized Radioactive Tree Long Sleeve T-Shirt. A tree made of radioactive symbols with a red and yellow glow is a humorous Christmas design. Fun holiday gifts for college students, physicists, nuclear engineers and workers. Pre-shrunk 100% cotton 6.1 ounce long sleeve t-shirt. Double-needle stitched neckline and sleeves. Quarter turned. Shoulder-to-shoulder taping. Adult: S, M, L, XL, 2XL, 3XL