Feature: 1. Premium Material: Stirling engine model is manufactured with high quality aluminum alloy materials and fine craftsmanship to avoid rust and prolong service life. 2. Wide Applications: Can be used as an excellent gift for children's science projects, physics or mechanical learning, classroom teaching props, and birthday gifts for friends, family, parents, children, etc. 3. Elegant 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. 4. Hand Made DIY: You can assemble with your relatives, friends or family and children, enjoy the fun of hand made DIY, and also enhance friendship and family affection. 5. Working Principle: Stirling engine converts thermal energy into mechanical work by circulating compressed and expanded air or other gases (working fluids) at different temperature levels. Specification: Item Type: Stirling Engine Model Product Material: Aluminum Alloy Color: As Pictures Shown Weight: Approx. 541g/19.1oz Remarks: Accessory Ethanol Bottle (Without Liquid) Scope of Application: for Children's Science Projects, Physics/Mechanical Learning, Classroom Presentations, etc.. Package List: 1 x Base3 x Hex Wrench1 x Ethanol Lamp1 x Ethanol Adding Tool39 x Accessories 1 x Sticker1 x Magnet1 x Chinese and English Manual