Every bike needs a seat bag. They&';re perfect for on-the-road repair essentials, your phone and credit cards, and a snack. Giant&';s Seat Bag DX features a stream-lined aero shape, water-resistant ProTextura fabric, reliable Velcro straps, and a built-in key holder. With its visibility-enhancing reflective accents and taillight hanger, you&';re sure to be seen in low-light conditions. The Medium, Large, and Extra large models have external side pockets for extra storage. The Large and Extra large models have an expandable zippered bottom panel.