Stainless Steel Impeller. For 1-1/2 in. shafts. 3/8 in. keyway. Blades: 4 in. W x 11-1/2 in. L. Recommended for low- to medium-viscosity, flow-controlled applications. Classic 45° pitched blade design. Produces a desirable balance of flow and shear. The impeller of choice in many standard applications. Overall dimensions: 24-1/2 in. dia. x 7-1/2 in. H.