This is a brand Blower Motor fits models. The specs are as follows: Vented, Med & Hvy Duty Rating Volts 12 Shaft Dia. 3/8″ Shaft Lgth. 4 1/4″ x 4 1/4″ Body Lgth. 4 1/8″ Total Body Lgth. 5″ Body Dia. 3 1/2″ Stud Ctr. Dist. 2 7/8″ Rotation Rev 3 Sp. Used On Models: COMBINE: 3300 COMBINE: 4400 COMBINE: 4420 COMBINE: 6600 (1971- 1974) COMBINE: 7700 COMBINE: 7720 Thanks For Your Business!! A-AH80194