Build a working model of a 4-cylinder engine, then hook up the cables to a battery box and watch the engine begin to turn. Watch the valves rock, spark plugs “fire,” and pistons drive the crankshaft! Features battery-operated moving parts and lights. A STEM poster explains how internal combustion gasoline engines operate and illustrates the four cycles – intake, compression, power, and exhaust. • Build a working model of a 4-cylinder engine. • Valves rock, spark plugs “fire”, and pistons drive the crankshaft. • Features battery-operated moving parts and lights. • Requires two (1.5V) “AA” batteries and a screwdriver (not included). • Ages 8+