The B40’s are based on Arkel’s time tested designs. They are built with the same attention to detail, the same materials, the same quality craftsmanship and the same lifetime warranty as all Arkel bicycle panniers. But they are built in their simplest form to offer top quality Arkel bags at a very affordable price. The B-40s are equipped with a manual hook system. Made of strong aluminum, this system is easy to use and there are no plastic parts that can bend or break. Built with nothing but quality and value in mind, these bags are really an incredible buy!