Build a working model of the solar system, called an orrery, then wind the crank to start the fascinating planetary show. The sun lights up and the planets rotate at different speeds. Kit includes 316 laser-cut wooden pieces that come in sheets, plastic planets, a multistage variable speed gear set, and a threephase brushless motor. No glue, tape, tools, or batteries required. Finished size: 13¾" high x 13" diameter