The three-blade narrow propeller impeller is a widely used axial-flow stirrer. Its blades are designed with a nearly equal-pitch curved surface, providing excellent discharge performance and low shear force. It generates a higher flow field in transitional and turbulent flow operations compared to other types. The discharge flow rate is 20% higher than that of a propeller-type stirrer. This impeller is suitable for mixing, dissolving, solid suspension, heat transfer, reaction, and crystallization of low-viscosity liquids. It is the best alternative for large mixing tanks to replace the traditional propeller impeller.