roswheel rear pannier bag for bike is best for carrying everyday essentials, extra clothes and camping gear on bike commutes, urban rides and long-distance tours. The pannier bag for bike offer roomy storage, protection from weather and the ability to quickly disconnect from a rack on your bike so you can take your gear with you. They attach to racks using a simple system of spring-loaded hooks, clips or bungee cords. They can be used singly or in pairs, and are designed specifically for front or rear racks.