Features_x005F_x005f_x005F_x000D__x005F_x005f_x005F_x000D_Hand boiler - boils the liquid with your own body temperature. Cup the lower chamber in your palm and watch how the liquid boils and rises through the tubes into the top chamber_x005F_x005f_x005F_x000D_Hand Boilers are looped and twisted glass sculptures containing a liquid that will "boil" as heat is transferred from your bare hand._x005F_x005f_x005F_x000D_Once out of your hands, it takes a few minutes for the liquid to cool down and return to the large bulb. It is a pretty fascinating science toy and an excellent demonstration of energy transfer._x005F_x005f_x005F_x000D_Hand Boilers come in several different colors including: blue, green, yellow, purple and red and several different loop shapes - yours will be randomly picked and shipped._x005F_x005f_x005F_x000D_Hand boilers demonstrate Charles"s Law and vapor-liquid equilibrium. The colored liquid in the boiler is comprised of a volatile mixture of liquids that have a boiling point just above room temperature. The body heat from your hand causes the liquid to boil, which in turn makes the liquid evaporate, turning it to gas. The expanding gas pushes the liquid upwards and when you release your hand, equilibrium is re-established. The gas condenses into a liquid again and flows back into the lower bulb._x005F_x005f_x005F_x000D_ Package include_x005F_x005f_x005F_x000D_1 x hand boilerOur products are made with the highest quality materials and are designed to provide you with the best possible user experience. We strive to ship out all orders within three days of purchase, and the estimated delivery time is 8-15 days.When shopping, please pay attention to the size and dimensions of the product to ensure that it meets your needs. In the title and , we have provided detailed information about the product, including its features and specificationsWe want you to be completely satisfied with your purchase, so if you have any questions or concerns, please don''''''''t hesitate to contact us. We are here to help and will do our best to assist you.Thank you for choosing our product. We hope you enjoy it