COMBUSTION MAIN IMPELLER 1” x 4 1/2”Blower Impeller, Exhaust 4.75" - 12 Petal. Enviro Part EF-008Fits Models:EF2, EF3, EF4, EF (Evolution), Empress FS & FPI, Meridian, Milan, Mini, Solus and Windsor.Shop Notes:old part # 880165021-PSP 4.75"PP7900-PSP