6 oz./yd (US) 10 oz./L yd (CA), 100% cotton, 18 singles Ash Grey is 99/1 cotton/polyester Heather Colors & Safety Colors are 50/50 cotton/polyester Antique Colors & Sport Grey are 90/10 cotton/polyester Safety Green is compliant with ANSI / ISEA 107 high-visibility standards Innovation you can feel. Made with 100% U.S. cotton and the latest breakthrough in soft cotton technology, the Gildan Ultra Cotton family has been remastered for improved printability, quality and comfort you can see and feel. Classic fit Rib collar Taped neck and shoulders for comfort and durability Tear away label PFD White: 100% cotton with cotton thread No optical brighteners - allows for more consistent dye adherence. Increased body and sleeve lengths to accommodate shrinkage. Proud member of the U.S. Cotton Trust Protocol Made with OEKO-TEX certified low-impact dyes. This product meets the following Sustainable Style subcategories: Sustainable Manufacturing: This product meets the OEKO-TEX Standard 100. Socially Conscious Manufacturing: This product was made by a mill who partnered with Fair Labor Association and was made in a facility that is WRAP certified.