Abstract: A device including an aluminum main body for a safety coupling is used for connection of at least one shaft and a drive wheel by way of, for example, a clamping hub. The device includes additional metal parts, namely a mounting flange, which is supported on the main body via ball bearings and is rotatable relative to the main body. One end face of the mounting flange can be connected to the shaft or the drive wheel in a non-positive manner, and the other end face of the mounting flange has indentations. Other additional parts include a steel bearing ring which secures the ball bearings on the outside of the main body via a retaining ring, locking balls disposed in the indentations, and an aluminum actuator ring which presses the locking balls in the direction of the indentations with force adjustable by an adjusting nut.