A system for emulating interaction with an interactive voice response unit is provided. The belt portions are provided with at least one element for identification and distinction of the different ends of the belt portions from each other. The device may be a medical device such as an endoscope or kidney dialyzer and a plurality of devices can be cleaned using the same composition. The clamping piece has one rod disposed at each end, with each end of the rod protruding through the receiving slot axially and being restrained by the confining part, thereby fixing the clamping piece and forcing the tool holder to move axially to facilitate easy switching and dismantling of the tool holders. The display means can be an analog or digital display or combination of display means.