Sport Grey is 90% ring-spun cotton, 10% polyester. Dark Heather is 65% polyester, 35% cotton.
There are alternate color options for Men's South Beach Pittie (Aqua, Pink, Ocean Blue, Heather Prism Ice Blue, Citron), Holy Shih Tzu Tripping Furballs (Aqua, Heather Prism Dusty Blue, Pink, Heather Prism Ice Blue, Citron), and Hypoallergenix (Yellow, Heather Prism Ice Blue).
The description for those colors:
Super-soft Airlume combed and ring-spun cotton. Pre-shrunk.
Solid colors are 100% Airlume combed and ring-spun cotton. Ash color is 99% combed and ring-spun cotton, 1% polyester. Heather colors are 52% combed and ring-spun cotton, 48% polyester. Black Heather is 90% combed and ring-spun cotton, 10% polyester.
