The International Harvester 666 is a 2WD utility tractor manufactured by International Harvester from 1972 to 1976. It is equipped with hydrostatic power steering, dry disc brakes, and has an option of an open operator station or a two-post ROPS. The tractor comes with one of two six-cylinder engines: a 5.1 L (312.0 cu·in) diesel or a 4.8 L (291.0 cu·in) gasoline engine and offers three transmission options: a 5-speed sliding gear, a hydrostatic transmission with infinite forward and reverse speeds, or a Torque-Amplifier 10-forward and 2-reverse partial power shift transmission.