Sigma = 21M summer pizza shirt slightly underground

slightly underground

waste-reducing construction

With a wide size range and many color choices

glitchy taco arcing across the chest with 'BTC: BILLIONAIRE TACOS CLUB' beneath — mixes retro arcade vibes with modern blocky glitch art

It settles easily into everyday rotation: throw it on with worn denim for city walks

Sigma = 21M summer pizza shirt slightly undergroundA heavyweight, garment dyed tee that feels lived in from the first wear. This relaxed fit shirt sports a clean, math inspired front graphic in warm orange on a soft natural ground subtle, clever, and quietly confident. The thick ring spun cotton holds its shape while the garment dye process gives each piece a slightly muted, vintage depth. It sits comfortably for long days of teaching, grading, or thinking through problems at the coffee shop. Sizes