A cleaning unit 1 for cleaning at least one head section of a milking cup, comprises a chamber 4 which is substantially circular in cross section and is delimited by a wall 6, with an opening which is delimited by a sealing element 3. The chamber 4 has at least one inlet, where at least one section of the wall 6 adjacent to the opening and a section of the sealing element 3 is designed to be elastic substantially in the circumferential direction of the chamber 4.
