Magnetic Field Viewer Viewing Film 2Style Card Magnet Detector Pattern Display L4MF Electromagnetic Radiation Detectors describe: This project is easy to use. place the card on the of a magnetic material and it will display a patterned magnetic field. Great for personal or scientific research. It can help us study magnetic fields that we cannot see. It can be used for quality control, product demonstrations, reverse engineering, certification and educational purposes. Small and portable, light weight, easy to carry. A wonderful educational tool to our interest in science. The Magnetic Field Viewer is a micro-encapsulated film that allows the user to see the static magnetic field. The highly flexible film is suitable for magnetic s with any convexity or cavity. Specification: Dimensions: 25*50mm,50mm*75mm Color: dark green Quantity: 1 piece The package includes: 1 x Magnetic Field Viewer Transition: 1cm=10mm=0.39inch Due to manual measurement, please allow 1-2 cm error. Make sure you don't mind before bidding. Due to differences between different monitors, the image may not reflect the actual color of the item. Thanks! _x000D_