This is the Solar Powered Car Assembly Kit from Tamiya.

FEATURES: Simplest and most basic example of a solar powered model.
Solar panel provides power for the motor, which drives the rear wheels.
Kit can be assembled by snapping and screwing parts together-no glue is needed.
0.5V-1200 mAh solar panel is mounted on a ball pivot to allow it to catch the sunlight efficiently.
Includes a choice of three gear ratios (1.7:1, 2.2:1 and 3.4:1).
Plastic parts are attached to sprue trees.
Motor and solar panel are included.
Detailed pictorial instructions.

INCLUDES: One Solar Powered Car Assembly Kit.

REQUIRES: Assembly
Hobby Knife
Side Cutter
Small Phillips Screwdriver
Adult Supervision

Using the Solar Car Assembly is a great way to experiment with gear ratios and the angle and intensity of solar light. With three gear ratios, high speed (1.7:1), mid speed (2.2:1), and low speed (3.4:1), you can see the difference gear ratios make under different conditions. The ball-mounted solar panel allows you to angle the panel towards or away from the sun, showing how direct and indirect solar light can affect power. Experiment under a variety of conditions (sunny, cloudy, etc.) and different gear ratios.