Personalized Mechanical Christmas Tree Toddler T-Shirt. A Christmas tree made of red and green mechanical gears is a humorous holiday design to tickle the funny bone of your favorite mechanic or mechanical engineer any time of the year. A toddler-soft cotton tee in look-at-me, big kid colors. 4.5 oz., 100% combed ringspun cotton. White is sewn with 100% cotton thread. Topstitched rib crew neck. Double-needle stitched sleeves and bottom hem. Shoulder-to-shoulder taping.