The ultralight RELO-Steckantrieb is an electric plug drive, compatible with all available types of bicycles. One always has the choice between normal bike operation and the use of the drive. The adaptive transmission is easily mounted to any bike. The battery and even the motor can be plugged in and off via a slight rotation by means of the patented bayonet catch. The operation is handled via Bluetooth LE® thumb switches on the handlebar – entirely wireless. The well-to-grip wankel shape of the battery and the motor clarifies the handling of the bayonet and shows their correct fit by positive fit of the shape. The design reduces the system to its smallest possible dimensions with a maximum of possible variable attachments (battery and motor can be installed on or under the down tube or to the seat tube). The components are visually aligned to the bicycle, the operation gets obvious. The housing of the gear wheels, for example, shows the position of the drive chains. The mounting variability is clearly readable. The design shows technical precision despite partially softer appearance and pleasant-friendly clarity.