The type 'G' Oilpull began production in 1918. This model was made until 1924 with 7,949 units being produced. Out of that number, 261 are known to survive. That's a 3.28% survival rate. The 'G' weighed 11,000 lbs. & was able to pull 30 HP on the drawbar & 46 HP on the belt according to Nebraska tractor test #11. It did this with its two cylinder, kerosene, 8 inch bore, 10 inch stroke, engine operating at 450 RPM. Other specs are available ON REQUEST. For more SN info on the 20-40, CLICK HERE.