Learn The Basics Of Electrical Engineering With The 4M Kidzlabs Traffic Light Activity Set .Build And Control Your Own Traffic Lights As You Prevent Road Chaos During Pretend-Play .Change The Lights From Automatic To Manual And Watch The Red, Amber And Green Lights Activate .Add The Traffic Lights To Your Favorite Train And Car Playset Scenarios .The Traffic Lights Measure 19 Cm In Length When Assembled .Requires 2 Aaa Batteries And Crosshead Screwdriver (Not Included) .Package Dimensions: 22 X 17 X 6 Cm .