Model DM115 Metal L4 Engine Kit is a 1/10 scale working OHV inline fourcylinder diesel model built from stainless steel and aluminum alloy with anodic oxidation finish. The kit combines realistic metal construction and a motordriven mechanism so you can assemble and observe a functioning engine model. Key benefits Realistic, durable construction: Metal components provide authentic weight and mechanical feel for a more accurate model and longer service life. Working demonstration: Motordriven design lets the engine run after assembly, allowing clear observation of pistons, crankshaft, and valve movement to illustrate how a real engine operates. Handson learning: Assembling 300+ parts following the included English paper instructions develops mechanical understanding, patience, and practical tool skills. Portable and usable: Compact finished size and onboard battery option make the model suitable for tabletop demonstrations and display. Main features Model: DM115 Scale: 1/10 Materials: Stainless steel and aluminum alloy Coloring process: Anodic oxidation Number of parts: 300+ parts Drive mode: Motor driver Power: External power DC5V via USB cable or builtin 450mAh Li battery Charging time: 2 hours Run time: Over 60 minutes at full power on a full charge Assembling time: Approximately 4 hours Difficulty: Fourstar difficulty suitable for ages 14 and up Finished dimensions: 18 x 9.2 x 14.5 cm Product weight: 1400 g Package dimensions: 20 x 20 x 15 cm Package weight: 2548 g Packing: Gift box Instruction: Paper English manual included What makes it stand out Metal parts and anodic oxidation finish give a feel and visible mechanical detail that plastic kits cannot match. The motordriven system provides dynamic simulation rather than a static display, turning assembly into a working demonstration of engine mechanics. Comprehensive kit with all parts and instructions enables a complete build experience from component handling to operation. Applications and use scenarios 1. Classroom and technical demonstrations: Use the running model to demonstrate piston motion, valve timing, and crank mechanism in engineering, physics, or vocational classes. 2. Hobbyist assembly and display: Spend an engaging build session assembling the 300+ parts, then display the finished working engine on a desk or shelf as a mechanical conversation piece. 3. Skill development and gift: Give as a learning gift for older teens and adults interested in mechanics; the kit teaches following instructions, part handling, and basic troubleshooting. What you receive All parts required for the engine assembly, motor driver, USB charging cable for DC5V external power, and a paper English instruction manual. The kit ships in a gift box and is intended for users aged 14 and older. This model provides a compact, handson way to explore internal combustion engine mechanics through realistic metal construction and a working motordriven demonstration.