The 4M green science windmill generator is a hand-on learning experience that teaches the value of renewable energy. The windmill generator uses Green science to harness wind power and light an LED bulb. This kit contains all the materials needed to build a 5" windmill generator with LED light. Details: 6.75" x 2.5" x 8.5" package size Includes materials to build 5" windmill generator with LED lightRequires a recycled soda bottle (not included) Enclosed pamphlet contains fun facts about renewable energy Detailed assembly instructions included For ages 5 and up