This is a simple stenciled shirt using a Sims 3 base game mesh. It fits young adult and adult male Sims. It appears under the "everyday," "sleepwear" and "athletic" categories, and includes several color variations. The "antisocial" stencil is NOT recolorable in CAS, but the rest of the shirt is. The shirt works just fine for even the most obese Sims.
The Sims3Pack version has a custom thumbnail in the launcher. The zipped file includes both a Sims3Pack and a .package file.