This is a self-made energy-saving experience device for environmental education, inspired by a similar set I saw at an environmental education site and thought I could use in environmental education at a company I used to work for. By rotating the attached "Zenecon" (hand-cranked generator, 10 units included), you can experience the energy-saving performance of incandescent light bulbs and LED light bulbs through the weight of the Zenecon's handle. The light bulbs can be switched between incandescent and LED with a switch. The number of bulbs can also be increased or decreased with a switch (2, 4, or 6 bulbs), allowing you to experience the change in load through the weight of the handle. This is a homemade item, so I will handle any malfunctions, but I cannot respond to other complaints. Therefore, this is for sale to those who understand this. A catalog on how to use the Zenecon is also attached. If you need other usage methods, please write them in the comments section, and I will include a memo of the methods I used in environmental education. Please note that although I have stated that it will take 4-7 days to ship, 5 of the Zenecons have gear damage. Therefore, I will order replacement parts after receiving the order and ship after the parts are replaced. Thank you for your understanding.