Call-a-Bike is a bicycle renting idea from DB Rent GmbH, which is being increasingly marketed in many German cities. This system enables the secure transport of durable as well as fragile luggage by bike. Durable, bulky baggage is placed on the luggage carrier and tightened with rubber straps. Tension springs are integrated in the strengthened inside walls of the basket, which are pushed outwards as soon as the basket is unlocked. When required, the opened unfolded basket can be closed by a flap and a click-lock to ensure that nothing falls out during a rough ride. The deposit lock is used to ensure that the basket is not alienated as a rubbish-bin after bringing the Call-a-Bike back. This luggage system can of course be used for the same flexible method of transportation on privately owned bicycles without the depository locking device.