Rib collar. – Antique colors & Sport Grey are 90/10 cotton/polyester. – Ash Grey is 99/1 cotton/polyester. – Taped neck and shoulders for comfort and durability. – Blackberry, Dark Heather, Graphite Heather, Heather Colors, Lilac, Midnight, Neon Colors, Safety Colors, Sunset, & Tweed are 50/50 cotton/polyester.