A suspension system for the attachment of a multiple bladed fan, connected beneath the roof of a canopy-styled tent or other overhead structure. The first holder is adapted to receive a first drug container having a first dimensioned shape but not a second drug container having a different second dimensioned shape. The circuit block has a current source that controls the gate voltage on the gate nodes of the one or more driver transistors and the circuit block as an additional first voltage source that provides the operating voltage of the driver circuit, in addition to a second voltage source that provides a control voltage which is used to adapt the driver circuit to different load magnitudes. In one embodiment, the human or operator cannot re-start the reaming process until the machine tool or reaming equipment is reset. The actuator is provided in the form of a double-contact actuator, whereby the contact steel plates are arranged inside a contact space that is closed at the top, and the contact can be actuated by a slide by moving this slide into a channel situated to the side of the inner space of the housing. The image is displayed based on image data included in the fetched image data blocks.