A mixer for generating a flow of liquid includes a stationary body, an axially extending drive shaft protruding from the stationary body, a propeller, and a clamping sleeve assembly configured to interconnect the drive shaft and the propeller with each other in order to transmit a rotational motion. The clamping sleeve assembly has an axial clamping length and includes an inner clamping sleeve and an outer clamping sleeve. The inner clamping sleeve has the shape of a tubular wall having an inner surface abutting the drive shaft and an outer surface abutting the outer clamping sleeve and wherein the outer clamping sleeve has the shape of a tubular wall having an inner surface abutting the inner clamping sleeve and an outer surface abutting the propeller. Both the inner surface of the outer clamping sleeve and the outer surface of the inner clamping sleeve are cylindrical along the axial clamping length.