A kit for building 5 engines: V8, U12, H16, X24 and a 42-cylinder radial engine. These educational models help you visualize how a piston engine works.Each model has a knob you can rotate with your hand to see the crankshaft and pistons move. No motor or battery box comes in the kit.The kit contains a large quantity of engine parts (102 cylinders and pistons). You can build all 5 models with this kit (instructions are included) or create your own imaginary or replica engines. The engines can be integrated into larger models, like cars and airplanes.Each model is a replica of a real engine (in essence, not in every detail):-V8 is a popular engine used in many vehicles-U12 engine was used in Sherman M4A2 tanks-H16 engine was used in the Lotus 43 racing car-X24 engine was used in the Avro Manchester heavy bomber-Radial-42 is similar to Zvezda M503 which was used in missile boatsSee all 5 models built and tested in the video below. More details about the models and how to build engines:https://brickexperimentchannel.wordpress.com/2023/10/24/lego-engine-models/