The Banjo Brothers' Grocery Bag Pannier is sized to perfectly accommodate a standard grocery bag. It attaches to any standard rear rack (sold separately) and folds flat when not in use. It's equipped with a strong steel frame and a rigid polymer liner. The front and side panels are ripstop with ballistic fabric in high-wear areas. It also includes a shoulder strap and a quick-release mount. So ride to the store, take your pannier inside, fill it with groceries, and reattach it to your rack. Shopping = done.