Mini Hot Air Sterling Engine Model Steam Powered Electricity Aerodynamics Science Education The product is shipped based on the color or size of the main image of the product page. Mini Hot Air Sterling Engine Model Steam Powered Electricity Aerodynamics Science EducationSpecifications: Material:metal,glass Color:Silver Size:165x87x95mm Features: Can effectively cultivate children's interest in learning Can also be used for classroom teaching and easy to understand. Note: When there is too much steam , the engine will stop working. Please set aside the inside and outside needle to reduce friction. Do not rotate the nut tightly, otherwise the glass will be broken. If the piston is cracked, you can be bond with glue. The alcohol lamp wick could not touch the glass and get to the hole so tightly. When pulling the piston, please do not force the front end, it is easy to break. Package include: 1 x Stirling Engine 1 x Alcohol Burner 2 x Spare Heating Tube