Here's one for all of you paleontologist out there. Or, well, at least all of you Jurassic Park fans. It's a blue shirt featuring a red drawing of the king of the Mesozoic era himself: the T-Rex. To purchase this shirt, check out the Amazon link below.
Featured on The Big Bang Theory episodes
S02 E17: "The Terminator Decoupling"
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S05 E15: "The Friendship Contraction"