6.8 oz. (US), 11.4 oz/Lyd (CA),100% Peruvian Pima cotton. Grey Heather is 90/10 cotton/polyester. Comfort of luxurious Pima cotton. Three Dura-Pearl button placket. Durable double-needle stitching on hem. Shape-keeping DuPont Lycra ribbed cuffs. Additional yarn in collar & cuffs for a neater appearance and greater durability.