Features: -Made of high quality materials, durable - Made of high quality materials, durable -The function is: shielding electromagnetic interference, anti-interference, passing EMC The product itself is not magnetic -Dimensions: 9.5 * 14.5 * 5.5, 9.5 * 19.5 * 5.5, 10 * 20 * 6.5, 11.5 * 25 * 5, 12 * 15 * 7.3, 12 * 20 * 6.5, 14.2 * 28.5 * 8, 16 * 28 * 9, 17.5 * 28.5 * 9.5, 10 * 10 * 6, (optional) -Quantity: 10pcs -Color: black -Product name: nickel zinc ferrite -Saturated magnetic induction: 400 -Initial permeability: 650-1000 -Rectangle ratio: 10 -Coercive force: 13 (A/m) -Residual magnetism: 150 (mT) -Curie temperature: 120 (℃) -Density: 4.9 (g/cm3) Package includes: 10 * Magnetic ring (optional) Notes: 1. Due to various factors such as display brightness and light brightness, the actual color of the product may be slightly different from the website picture. 2. Please allow a slight deviation between the data and the manual measurement. Circular Anti-interference Magnetic Ring Ferrite Core Magnetic Ring Shielding Materials: Made of high quality materials, robust and durable, safe and convenient to use. Size: matched to the corresponding model to match your working tool needs, check if it is the size you need before you buy. Function: This is a good companion you need on your tools, giving you a more convenient working life, in case you are busy indoors and outdoors Satisfaction guarantee: Your purchase is fully protected when you order today. If you are not satisfied with with our products, contact us any time, We will get you back within 24 hours try our best to make things right.