The bottom plate is made of metal, exquisite atmosphere; the bracket is made of zinc alloy casting, which is stable and strong; the flywheel and cylinder liner are made of aluminum alloy precision turning, precision milling, and the texture and beauty are combined; the connecting rod is made of stainless steel; the cylinder and piston are glass The material is transparent and intuitive; the overall model is exquisite, atmospheric and beautiful; the demonstration principle is intuitive and clear. All the wheel and axle connections are connected by high-precision miniature bearings, and the shaft sleeve is precision polished with brass, which is stable and does not require lubrication.