Castelli Core Seamless Base Layer SSStretch and Comfort Base layers are perfect for adding an extra layer during those cooler days out on the road. The Castelli Core Seamless Base Layer SS is made of polyester and polypropylene yarns that are soft, breathable, and wick moisture to keep you dry while you ride. This base layer features seamless construction, which means extra comfort and a wide neck opening allows this base layer to fit under short-collared jerseys. Features Polyester and polypropylene blended fabricis lightweight breathable, moisture-wicking Seamless construction gives the exceptionally stretchy fit Weight 151 grams SPECIFICATIONSMaterial84% polyester / 16% polypropylene yarns Sleeve Length Short Closure Type None Fit Regular Sizing Size Small/ Medium Large /Extra Large2X Large Chest (in)36-37. 539-4143Waist (in)31-3334. 5-36. 538. 5 | Castelli | Core Seamless Base Layer Ss Men's | Size Xx Large In White | Polyester