Wind Power Science Kit. Build wind-powered generators to energize your electric vehicles. Kit includes 2 styles of wind turbine blades and a gearbox with three different gear ratios for experimenting. You can adjust the angle and number of wind turbine blades to make best use of the wind, to make the LED light up brightly, and to charge the rechargeable batter as fast as possible. Includes 133 pieces, can make 8 models. 40 page manual included. For ages 8 and up. Box measures 14.5" x 11.5".