Follows the shape of your body, with some breathing room for unrestricted movement; Fluorescence, high contrast, and reflectivity in critical motion zones help runners be seen in the dark; Breathable GO2 Warm fabric with 80g THERMOLITE synthetic insulation traps heat; Remains lightweight, providing warmth without weighing you down; Two front zip-secure pockets store valuables; Right pocket features a stash pocket for smaller items