Single, small sized solar cell unit Unit has (2) 4mm plug terminals Capture the suns energy with the solar cell and connect to mini motor (not included) to generate enough power to operate a small propeller Unit measures 4" wide, 3" long and 1" tall. Solar cell panel measures 3" by 1.25". Great tool for science projects, as well as energy conversion and electrical circuit demonstrations Capture the suns energy with the solar cell to transfer electricity with this small solar cell unit. Fun and educational experiment tool for energy conversion and electrical circuit demonstrations Compatible for use with Eisco Labs PH1319 Mini Fan Motor Unit (not included). Can be connected using two, standard 4mm banana plug connection leads, such as Eisco Labs PH1055EF. Unit measures approximately 4" wide x 3" long x 1.5" tall. Solar panel measures 3" wide by 1.25" long. This solar cell does not operate indoors. Must be used with natural sunlight for units to work.