Endorsed by Haynes (World's No. 1 publisher of Car Repair Manuals). Construct a fully working model of a car engine with ignition sound and light-up spark plugs. These models are fun and challenging to put together. Both kits contain all the tools you'll need to assemble over 100 detailed and precise parts of this working model. Includes and electric motor to stimulate engine function and a clear step-by-step Haynes Manual to assist intrepid mechanics and motorheads. Requires two AA batteries.