The KT-4 was the first Kristi to have an available Chevrolet Corvair engine.  Built with either the 65hp Porsche Marine engine or the 80hp Corvair engine, this Kristi weighed in at 3080 lbs with a full cab. Seating increased to 6-8 adults plus the driver; there is seating for two passengers on each side of the driver in the front and side facing bench seats in the rear.  The engine was mounted mid-ship and was enclosed to keep all of the working parts away from the passengers.

The KT-4 vehicle had a 4-belt track design with standard hickory cleats. The exhaust on a KT-4 exited the rear of the vehicle.

The amphibious KT-4A can be identified by the following characteristics: the intake and exhaust ducts exit the top of the vehicle; the tracks on the KT-4A were a two-belt design with every cleat extending the full width of the track; and the sides of KT-4A had a rubber skirt that helped to propel the vehicle in water by preventing water diversion around the track when in the up most position.

The following is a filtered view of the official Kristi vehicle logbook displaying the KT-4 and KT-4A models.