Product overview This preassembled model demonstrates the basic structure and working principle of a fourstroke singlecylinder engine. Designed for middle school physics course experiment teaching, it is compact, durable, and easy to operate by hand or with a simple battery power supply. Key benefits Clear visual explanation of engine operation: Shows intake, compression, power, and exhaust strokes to help students understand how a fourstroke singlecylinder engine works. Ready to use: Supplied fully assembled so teachers and students can begin demonstrations immediately without setup. Flexible operation: Can be run manually for slow, observable motion or powered by 2 x 1.5V AA batteries for continuous demonstration. Batteries not included. Portable classroom demonstrator: Compact size and light weight make it easy to move between classrooms or lab stations and convenient for tabletop demonstrations. Durable mixed construction: Combination of plastic and metal parts balances visibility, ease of handling, and component strength for repeated classroom use. Main features and specifications Function: Model of a fourstroke singlecylinder engine for teaching and demonstration Operation modes: Manual or battery powered Power: 2 x 1.5V AA batteries required, not included Material: Plastic and metal construction Base length: Approx. 17 cm / 6.69 inch Width: Approx. 11 cm / 4.33 inch Height: Approx. 30.5 cm / 12 inch Weight: Approx. 766 g Condition: Preassembled for immediate use Package includes: 1 x Engine Model Practical use scenarios Classroom demonstration: Use during a middle school physics lesson to illustrate the fourstroke cycle step by step while students observe moving parts and timing. Lab experiment and group activities: Small groups can operate the model manually to trace piston movement, valve timing, and crankshaft rotation, reinforcing theoretical lessons with handson observation. Teacherled presentation or science fair: The compact, freestanding design makes it suitable for table displays and teacher demonstrations that require a visible, working model of engine mechanics. Why choose this model for teaching This engine model focuses on clarity and usability. It presents the core mechanical concepts behind a fourstroke singlecylinder engine in a compact, durable package that teachers and students can operate immediately. The two operation modes allow controlled observation as well as continuous demonstration, making it a practical tool for a variety of instructional settings. Note Batteries are not included. The model is intended for demonstration and educational use in middle school physics courses.