The Disney Cars 3-Book Play-a-Sound Library invites children to join Lightning McQueen and his friends from the Disney movie Cars pals on three new adventures. The set, designed for children ages 18 months and older, is comprised of three storybooks and an interchangeable five-button sound strip. Snap the sound strip onto any of the three books to hear familiar sounds as a story is read.Lighting Speed tells the story of an international race being held in Radiator Springs. Matching illustrated icons on the pages with the corresponding sound button activates the following: Race starting signal Tires being changed Glug of an oil can Revving car engines Cheering race fansNight Vision tells of the nighttime race that takes place after Mater is frightened by the new race car Gudmund hiding in a cave in Radiator Springs. Pressing the sound buttons activates the following: Spooky tune Honking horns Revving car engines Night vision goggles activating Lightning and Gudmund zipping around wicked curvesBuilding the Town tells the story of how Radiator Springs was built by or tornado-like dust devil. Pressing the sound buttons activates the following: Traveling song Whipping sound of the dust devil Hammers and saws at work Police sirens Splashing waterThe Disney Cars 3-Book Play-a-Sound Library conforms to the safety requirements of ASTM F963-07. The book has been safety tested for children 18 months and up. Three replaceable long-life AG-13 button cell batteries that power the sound strip are included. - from Amzon