M16-22-D Dual-Cylinder Parallel Full-Metal Stirling Engine Generator Model, Matte Black External-Combustion Engine for Power Generation and Collector Gift

【Dual-Cylinder Parallel Drive】: Two cylinders work simultaneously for stronger torque, smoother rhythm, and enhanced operational stability. 【Full Metal Construction】: All-metal CNC-machined components provide durability, precision, and a premium matte black appearance. 【High-Efficiency Power Generation】: Converts thermal energy into electricity to light the included bulb, ideal for energy conversion demonstrations. 【External Combustion Display】: Open mechanical layout clearly shows piston linkage, flywheel rotation, and heat-cycle dynamics. 【STEM & Collector Value】: Suitable for science classes, engineering demonstrations, hobby collections, and premium mechanical gifts.