1Premium Material: Stirling engine model is manufactured with high quality aluminum alloy + stainless steel + solid wood materials and fine craftsman to avoid rust and prolong service life. 2Simple Operaton: Fill an ethyl burner with 95% athyl and light it. Let the lamp burn the circular cylinder for about 20 seconds, then gently push the wheel and stirling engine will run like a charm. 3Wide Applications: Can be used as an excellent gift for children's science projects, physics or mechanical learning, classroom teaching props, and birth gifts for friends, family, parents, children, etc. 4Working Principle: Stirling engine converts thermal energy into mechanical work by circulating compressed and expanded air or other gases (working fluids) at different temperature levels. 5Elegant Gift Packaging: Hot air stirling engine motors are an amazing and dreamy product. Its elegant gift packaging makes it gorgeous and stylish, having a wide range of applications. Item Type:Stirling Engine Model Product Material: Aluminum Alloy + Stainless Steel + Solid Wood Color: As Pictures Shown Weight: Approx. 458g/16.2oz Remarks: Accessory Ethanol Bottle (Without Liquid) Model Product Size: Approx. 18x9x9cm / 7.1x3.5x3.5in Scope of Application: for Children's Science Projects, Physics/Mechanical Learning, Classroom Presentations, etc. 1 x Engine Model 1 x Ethanol Lamp 1 xEthanol Adding Tool 3 x Hex Wrench 1 x Sealing Ring 1 x Needle Roller 1 x Silicone Tube 2 x Accessories 1 x Chinese and English Manual