DuroMax XP16HPE 16 hp Electric/Recoil Start Engine Max Torque: 28.5 Nm/21.0 ft./lb. Maximum 16 horse power EPA approved 4 stroke engine with electronic ignition Air Cleaner: Dual, Semi-dry, Oil Bath Shaft Size: 1 in. Diameter , 2-3/4 in. Long, 1/4 in. Keyway, shaft end drilled & tapped with 3/8 in. 24 UNF Dimensions: 20.47 in. L x 18.5 in. W x 22.0 in. H Electric and Recoil Start