The welding electronic kit not only contains electronic knowledge, but also uses physical knowledge. Electromagnetic swing uses the principle of electromagnetic induction, and the Hall element, magnet and magnetic field affect each other to drive the swing of the magnet pendulum needle. If you are interested in physics, this DIY welding product kit let you enter the physical world, and the swing let you discover the mystery of physics. There are colorful LED lights embedded under the leaves. When the switch is turned on, the pendulum needle begins to swing under the vibrant leaves, creating a charming scene. The red, yellow and green LED lights on both sides of the coil are carefully designed by a single switch. Together with the swaying pendulum needle and the flashing lights on the leaves, it is like a ship ready to sail. This DIY welding kit helps you understand some basic working knowledge of printed circuit boards and become familiar with electronic components; you can enjoy an interesting welding experience with your students, or you can practice your welding skills. A unique welding experience allows you to get interesting electromagnetic decorations; the special leaf shape and swinging magnet needle become a unique decoration on the table, attracting people's attention; it can also be a meaningful gift to impress friends and relatives. Note: Tools may be required when installing the pendulum pins. Material: Metal Color: As shown Package Contents: 1 set soldering practice kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.