Black Waterproof Multi Function Excursion Cycling Bicycle Bike Rear Seat Trunk Bag Handbag Bag Pannier Carrying Luggage Package Pack It adopts waterproof polyester material, solid and durable Size information:322817cm(12.6inch11.02inch6.7inch Not Extend),32(H)25(W)5cm(12.6inch9.84inch1.97inch Extend) Large extension capacity,with shoulder strap and rainproof cover,With a main pocket, Two insert pockets and a bottle pocket Wide sliver grey reflective stripe, it is safe to ride at night Matched with straps, can be used as a handbag and shoulder bag,it is convenient for you to carry when you are not bicycling