The dosing device (1) has rotary or slide dosing units, and supply and delivery terminals which are opened and closed. The changeable volume of the dosing units is filled with a substance which is to be delivered by the terminals. The supply and delivery terminal has an opening of dosing unit. Independent claims are also included for the following: (1) a system for the delivery of a substance with the dosing unit (2) a method for dosing a substance.
