Abstract: Apparatus for mixing and dosing at least two synthetic resin components to produce a single product includes a mixing head wherein the components are mixed together to form the product which is subsequently discharged. The mixing head includes a casing with an end port. A rotor drive shaft has a drive end extending out of the end port. A hollow mixing chamber which receives the components has a connection port adapted for detachable connection with the end port. A first quick connecting-disconnecting coupler mounted partially at the casing and port and partially at the chamber connection port detachably connects the casing to and disconnects the casing from the chamber. A rotor mechanism includes a mixing rotor disposed in the chamber. A second quick connecting-disconnecting coupler is mounted partially on the drive end of the shaft and partially on the rotor detachably connecting the shaft to and disconnecting the shaft from the rotor.