Features: 1.Rhombus Small Magnetic Needle with Stand Physical Experiment Teaching Instrument. 2.Uses: 1. Demonstrate the magnetic line spectrum of the linear current magnetic field, indicating the relationship between the magnetic field direction and the current direction. 2. Demonstrate the magnetic line spectrum of the toroidal current magnetic field and their polarities. 3. Demonstrate the magnetic line spectrum and polarity of the magnetic field of the energized solenoid, indicating the right-hand rule of the direction of the magnetic field line. 3.Suitable for middle school, technical secondary school when conducting experiments or student experiment in group. 4.In order to ensure the use time of the small magnetic needle, please avoid the magnetic pole and magnetism of the strong magnetic needle. 5.Simple structure, easy to operate and clean. specification:Condition: Brand New Item Type: Small Magnetic Needle Quantity: 16pcs PackageList:16 x Rhombus Small Magnetic Needle16 x Plastic Stand