Composition - Neodymium magnets are composed of neodymium (Nd), iron (Fe), and boron (B). The crystalline structure makes the magnets more fragile than carbon steels. Feature - These magnets are coated with Nickel+Copper+Nickel that offers a shiny surface and durability for rusty resistance. Applications - These magnets are used for educational, research, professional, commercial, or industrial purposes that are sold to school educators, researchers, professionals, or commercial or industrial users only. Avoid Breaking - Always slide off a single magnets from the stack when you need to use, slide onto the stack with soft spacer to avoid potential breaking. Realth Mangets - we offer neodymium magnets in different size for educational, research and industrial purpose, also we have magnetic sheet, like magnetic canader buddle sheet, dry erase magnetic sheet, magnetic business cards, magnetic label holders and so on. SIZE:10cm*6cm*5cm