Retrol Steam Engine Model Kit, Mini Horizontally Opposed 4-Cylinder Engine with Gearbox for Small Steam Model Ships Without Boiler for Physics Experiment Display

⚙️【Industrial-Grade Compact Power】Features a horizontally opposed four-cylinder design (8mm bore/stroke) and Walschaerts valve gear for efficient steam conversion. Includes a 1:1.44 ratio gearbox with clutch release fork for forward/reverse control (3kg/cm² pressure) 🚤【Ideal for Marine Models】Designed for small steam ships (boiler not included). Low-power compatible (suits 50x100mm boilers) with φ4mm copper pipe connections. Perfect for powering boats, car models, or mini generators 🔧【Easy Maintenance & Assembly】Removable structure simplifies lubrication (steam oil required) and part replacement. Includes a nut-type lubricator and φ3mm stainless steel crankshaft for durability 🎓【STEM Learning Tool】Demonstrates thermodynamics, mechanical motion, and nautical engineering. Ideal for hobbyists aged 16+ to explore steam power principles and gear transmission mechanics 🎁【Retro Industrial Collectible】Polished metal construction (350g engine + 120g gearbox) with brass gears. A striking desk display or gift for ship modelers, engineers, or steam enthusiasts