Fagus Escalator Marble Run. Turn the crank and this will turn the axle with the misaligned mounted wheels. These wheels move the tappets up and down and in this way the marbles are transported step by step up towards the top of the escalator. Once at the top they roll down the slope to the beginning of the escalator and the process can start again. Comes with five glass marbles. Recommended from 3 years.