Super-lightweight construction with just enough warmth Low/no collar for temperature regulation Castelli FLY Fabric Technologies: FFT Fly T-SL fabric YKK Vislon zipper 3 back pockets with zippered security pocket for valuables Elastic and silicone at waist to keep jersey in place Reflective tab on back pockets Weight 304 g (M) 12-18°C / 54-64°F