An attachment part with a coupling part by means of which coupling part the attachment part can be attached to a dispensing unit. The coupling part has a female cone area, with a continuous inlet opening, and a locking structure arranged around the female cone area. The female cone area can be pushed onto a male cone area of the dispensing unit, in order thereby to connect the attachment part to the dispensing unit. The locking structure serves to secure the attachment part on the dispensing unit. The first coupling part additionally has a rotation element, which is rotatable concentrically about the female cone area and on which the first locking structure is formed. The rotation element has an actuating element, which serves to rotate the rotation element relative to the female cone area.
