The Sutton Skunk was a little-known tractor tank from early 1932, built for the Chinese export market by Frank ‘One-Arm’ Sutton (Englishman and adventurer). It was simply a Caterpillar 5-ton M1917 tractor that was borrowed from the military and armored up. Featuring two 82mm Stokes mortars and a pair of Browning machine guns. 1 Prototype Built.