The Banjo Brothers Grocery Bag Pannier is sized perfectly for a single paper bag. It attaches to any standard rear rack and folds flat when not in use. Built to last, it's equipped with a steel frame and a rigid polymer liner to prevent sagging, and the front and sides are ripstop with ballistic fabric in high-wear areas. It also includes a shoulder strap and a quick-release mount. So ride it to the store, pop the pannier off the rack, shop with it and reattach it to your rack. Shopping = done.