The Snap Circuits® set makes learning electronics easy and fun! It includes building blocks with snaps that enable young experimenters to build different electrical and electronic circuits. Each block has a function: there are switch blocks, lamp blocks, battery blocks, and different length wire blocks, to mention a few. These blocks are in different colors and are numbered for easy identification. Sets come with complete instructions to build many different circuits and are available in 3 sizes. Each set requires 4 AA batteries (not included). Includes over 30 part, 100 projects.