The Snap Circuits Mini Space Battle kit features brightly-colored electronic components that snap onto a clear plastic base to build different circuits. With this kit, you can build a sound machine that plays an exciting range of sounds, as if a space battle is raging! Activation occurs via a combination of a switch and a photoresistor that detects motion. Includes 3 additional projects: Double Space Battle, Touch Space Battle, and Photo Space Battle. Requires 2 AA batteries. Includes a colorful and easy-to-follow instruction sheet that make these electronic experiments easy and fun to build. Fun Fact In movie studies, technicians are paid to insert sounds like these at the precise instant a gun is fired. Try making your sound occur at the same time an object hits the floor. It's not as easy as it sounds!