Structural Integrity is Not a Joke. (But this Shirt is.) Show the world you understand static equilibrium with this brilliantly simple design. Featuring a classic three-stone structure, this shirt speaks volumes about physics and stability. Whether you're an engineer calculating loads, an architect designing support, or just someone who appreciates a well-built pun, this shirt supports your sense of humor. Great for work, engineering class, or casual wear! Celebrate the power of engineering—the world needs problem solvers! Men's/Unisex Sizing: RUNS SMALL This shirt is made from soft ring spun cotton. Solid Colors Are 100% Cotton Vintage colors are 50% cotton/poly blends. Sport Gray is 10% polyester. Tear Away Tag RUNS SMALL Please note sizing may be +/- 1" in either direction. It is side seamed and should be considered fitted. We always recommend ordering 1 size up for those who love a loose, boxy tee. See images for size information.