Their tractor trucks included a large belt pulley that could be attached to the front crank shaft, useful for powering grain separators and other belt-driven machines. Early models had cast steel wheels with holes. Wooden plugs were driven into the holes to provide added traction.
The tractors of this era included a large belt pulley that could be connected to the front crankshaft, making them suitable for driving grain separators and other machinery using belts.  Early versions had cast steel wheels with holes, which were filled with wooden plugs to improve grip.