New Threaded Impeller Kit fits Johnson F5B pumps. Contains aftermarket parts Includes: Impeller with internal threads O-ring (2) Gasket (4) Impeller Specifications: Width: 1-1/4" (31.5mm) Diameter: 2-1/4" (57mm) Shaft: 5/8" (16mm) Drive: 12 Spline Material: Neoprene Silhouette: 12 blades