Extremely lightweight & packable this "emergency" jacket can save your ride-and your hide-in sudden downpours or unpredictable weather. Stuffs easily into jersey pockets or seatbag though its generous ventilation panels make it suitable to wear all day. Ultra lightweight woven polyester has a durable water-resistant finish Strategically placed stretch mesh panels increase breathability & stretch fit Reflective trim on lower back for visibility Binding at waist helps keep jacket in place Form fit sizing