This is a Stirling engine model made by the Vintage model workshop chaired by Mr. As far as I know these are the smallest scale model stirling engines ever made - until you make one smaller. Name: Hot Vertical Stirling Engine Model.
Material: Brass + Stainless Steel + Aluminum. Flywheel Diameter: 29mm (Including Pulley). Product Dimensions: 62x 42x 72mm.