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• Description
• Size Chart

• A clever and unique birthday present with a 🌈 rainbow twist!

  The original countdown t-shirt, but in rainbow colors! This one of a kind t-shirt is mathematician approved, with all leap years accounted for. Serving any and all ages!

   

  If you have a loved one that's celebrating a birthday and totally awesome, you're going to love giving them this fun shirt to wear on their special day! They will be sure to receive many compliments.

  This product is custom and not created until the order is processed. Please include your desired age before adding to cart and our mathematicians will get to work on your custom calculated t-shirt!

• Toddler	2T	3T	4T	5T	6T
  Weight (lbs)	30-33	33-36	36-40	40-45	45-50
  Height	32-35"	35-38"	38-40"	40-43"	43-49"

  Youth	XS	S	M	L	XL
  Sizes	2-4	6-8	10-12	14-16	18-20
  Weight (lbs)	45-65	60-80	75-102	102-122	122-140
  Height	43-49"	49-54"	54-61"	61-65"	65-67"

  Adult	S	M	L	XL	2XL	3XL
  Length	27"	28"	29"	30"	32"	33"
  Width	18"	20"	22"	24"	26"	28"