White: 100% combed and ring-spun cotton, 30 single 4.2oz. (Ath. Heather - 90% combed and ring-spun cotton 10% poly; Dark Grey Heather and Deep Heather - 52% combed and ring-spun cotton 48% poly) 

Mineral Wash*: 100% cotton, 32 single 4.4 oz.

*Disclaimer: Due to the specialized washing process, each shirt is unique