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 warranty as all Arkel panniers. But they are built in their simplest form to offer top quality Arkel bike bags at a very affordable price. The attachment system consists of a bungee, nylon cushioned aluminum hooks and manually operated locking swivel. Built with nothing but quality and value in mind, these bags are really an incredible buy!