From the product description, check product page for current description, price and availability:

• STRONGER THAN THE COMPETITION – Made from the strong magnetic element, our pure neodymium disc magnets are incredibly powerful. This set of premium rare earth magnets can handle your project or task.
• UNMATCHED QUALITY – Your safety is our highest priority. Chipped, broken magnetic shards are dangerous. We use thicker, industrial grade, durable N45 grade neodymium rather than extremely brittle N52 used by our competitors.
• PREMIUM QUALITY COATING – You will love the smooth and shiny finish. Our magnets are protected with a corrosion resistant Ni-Cu-Ni (Nickel-Copper-Nickel) coating to create a high quality silver look that doesn’t rust or scratch.
• UNLIMITED USES – No matter your application, our powerful magnets can handle the job. These thin magnetic discs work great as strong refrigerator magnets, arts and crafts, DIY projects, hanging spice jars, pictures, whiteboards, tools in the garage, or science classroom at school.

From HBF: Make sure the components you use are compatible and rated for your intended application.  Contact manufacturer with questions about suitability or a specific application.  Always read and follow manufacturer directions.