Σετ εργαλείων
Gelsonlab HSTM-059 Education Science Toys Σετ εργαλείων experiment
This Σετ εργαλείων uses rack, belt, turbine, vortex rod, umbrella gear, flat gear and other transmission modes, through experiments to understand the advantages and disadvantages of various transmission devices, such as noise, transmission ratio and change of transmission direction.