The item is a kit of physics experiment props, adoption of durable magnet material. Easy to use and operate, it is suitable for personal and professional use. Suitable for university, school, laboratory, and so on. Features -Color:Transparent -Material:Plastic, magnet -Size:15.20X10.50X2.00cm/5.97X4.13X0.79in - Adoption of good magnet material, sturdy and durable for long-term use. - Let cultivate interest in learning and improve grades through practical exercises. - With this teaching instrument, you can explain the right-hand rule and the relationship between the field direction and the direction. - You can demonstrate the field pattern of straight lines, loops, solenoids, and . - It makes students easier to learn the knowledge in the book more specifically. Package list: x Magnetic Needles 1 x Storage Box