Features:DIY unassembled Stirling model kit, enhance hands-on ability, experience the fun of assembly The size after assembly is 12x9x13cm/4 7x3 5x5 1in Made of high quality metal, enabling the model sturdy and durable Metallic texture and unique flying saucer appearance make it an eye-catching desktop decor Fuel is anhydrous ethanol or 95% medicalalcohol Ignite after filling the fuel, wait for the water to boil, then gently push the flying saucer, it will start to rotate Water needs to be added to the flying saucer to produce steam to make the it rotate, very easy to operate Mute design, give you a comfortable environment and don't disturb others A fantastic gift for kids' science project, Physical/mechanical learning, teachers Demo props on the class, inspiring children's interest in science and physics learning Specifications:Material: MetalModel Size: 12 * 9 * 13cm/ 4 7 * 3 5 * 5 1in(Assembled)Package Size: 17 5 * 12 * 5 5cm/ 6 9 * 4 7 * 2 2in(Unassembled)Package Weight: 441g/ 15 6ozNote:1 The fuel needs to use anhydrous ethanol or 95% medicalalcohol 2 The flying saucer needs water to produce steam to make it rotate 3 The package does not contain alcohol You are required to purchase by yourself Please understand the inconvenience Packing List:1 * Stirling Engine Model Kit1 * Assembly Instructions