The board, which measures 24 cm x 8 cm, has four gear trains made up with gears of 10/20, 10/30, 10/40 and 20/40 teeth. This gives gear ratios of 1/2, 1/3, 1/4 and 1/2.

A plastic track held in two linked runners. The short track can slide in the grooved runner while the long shallow slope can be set (using the support bar) so as to have the the target ball sitting at the start of the scale, which is inside the plastic track.