This suction cup, called Plopper, has many functions: toilet paper dispenser, door knob, towel hook, etc.
The design was conceived in 1998 following a workshop at the Eindhoven TU. The regular transparent suction cups irritated me because the metal hook kept making holes in tea towels, for example. The solution to this was to make the entire unit out of the same material. Over time the Plopper took on more functions.
Dimensions:  Ø 9 cm
Material: plastic
Photography: Rob Acket