It says 97% supima cotton, 3% elastolefin (not 100% supima cotton) but it feels like something between polyester and polyethylene.
H2H Mens Casual Slim Fit Short Sleeve T-Shirts Cotton Blended Soft Lightweight V-Neck/Crew-Neck
46 Review
π Nantersan Placket Raglan Tee - A Casual Must-Have
52 Review
INFLATION Bamboo Shirts Sleeve Elastic Men's Clothing in Shirts
45 Review
Men'S Long Sleeve Polo Shirt - Slim Fit, Stretchy, Breathable Collar
43 Review