Sierra International Impeller For Johnson Pump 3 3/4in D x 3 1/2in.W 3-3/4in D x 3-1/2in W 18-3304. The impeller features a 3-3/4" diameter and a 3-1/2" width. Includes (1) Impeller and (1) Gasket per package. Constructed of durable Neoprene material....