Note: the cream colored drive wheel is the distiguising aspect that identifies this as the first variation of this toy. Later versions has a wheel that has a rubber gasket around the metal wheel.
Another distinguishing feature that identifies this toy as the first version is the use of the ball bearing in the front of the toy. The ball is used to keep the horizontal wheel seen in the center from touching the table. When the toy goes over the edge and the ball bearing is no longer touching anything the horizonatal wheel then moves the toy to the right allowing the toy to stay in motion on top of the table, thus completing the "tricky" action.