Abstract: It is often necessary to manufacture casting masses out of several components which must be homogeneously mixed in a specific ratio. It can thereby happen that such casting masses harden so quickly that they must be processed in the shortest time possible in order not to react with one another or harden already in the mixing area or in the pipelines and thus result in the possible destruction of the device. The components are in the arrangement of the invention each moved by a pump out of the respective storage tanks into a synchronous dosing mechanism which consists of a dosing chamber for each component, from where the respective now dosed amount of each component is moved with the help of a dosing piston into a flow mixer, with the dosing pistons being thereby mechanically connected and operated by a common drive, and the flow mixer moving the now ready casting mass directly into a mold. The mixing ratios can in this manner be well maintained.