A carding element (3) on the periphery of a carding or cleaning roller (1) is arranged to be movable in the direction toward or away from the roller (1) and is movable to selectively present different types or sizes of clothing elements (14.1, 14.2, 14.3 and 14.4) in proximity to the roller (1) so as to effect different actions on the fibers as the clothing elements on the carding element function as counter clothing elements for the clothing (12) of the carding or cleaning roller. This facilitates optimization of the cleaning function obtainable through the cooperation between the clothing (12) on the card drum and the clothing elements (14).
