4.5 oz., 100% preshrunk ringspun cotton jersey; Dark Heather, Heather Navy, Heather Orange, Heather Purple, Heather Royal are 65% polyester 35% cotton; Antique Cherry Red, Antique Heliconia, Antique Sapphire and RS Sport Grey are 90% cotton 10% polyester;Seamless double-needle 1/2" collar; Taped neck and shoulders; Sideseamed; Double-needle sleeve and bottom hem; Tear away label; Gildan's manufacturing process utilizes 45% renewable energy; Gildan’s Community Investment Program supports education, the environment, humanitarian aid and active living in the communities we do business in;