Not only is this Maverick bag made for all weather conditions, the reflective 3M zones will also enhance your visibility on darker days and at night. Just fasten it around your chest and waist and it keeps your things dry and safe while you enjoy your ride. Need some extra storage place? Use the expendable layer to take everything you need with you on your bike. Features Backpack with expendable storage layer. Volume: 21 L Dimension: 31.5*15.5*52.0 cm Reflective 3M zones Chest and waist fastening system With rain cover Technologies waterproof and breathable membrane. 3M Thinsulate insulation is warm yet lightweigt, powerful yet thin. It helps trap body heat, while allowing moisture to escape.