Provide a source of uniform velocity at an affordable price! Engage students in dimensional analysis with a 2-speed, battery-operated car. On a flat surface, the car travels at a constant velocity in a straight line long enough to conduct most standard time-and-distance experiments. Car body measures 4 x 7 x 3". Requires 2 C or 2 AA batteries (not included). Instruction manual includes sample labs and suggested extensions for advanced students.