CERAMIC COMPOSITION: These ring magnets are crafted from ceramic ferrite material, known for its high resistance to corrosion and demagnetization. Excellent for indoor and outdoor use. 2.17 LB Pull Force VERSATILE: Suitable for various applications, including crafting, education, DIY projects, and small-scale experiments. Glue to the back of heavy-weight projects to make them magnetic. ECONOMICAL: Ceramic ring magnets are an affordable option for those seeking reliable magnets without the expense of more advanced magnet materials. HIGH TEMPATURE PERFORMANCE: Ceramic ring magnets offer excellent stability and strength in high-temperature environments up to 400 degrees Fahrenheit. MASTER MAGNETICS: We manufacture magnetic products for commercial, industrial, and consumer use. Our goal is to create reasonably priced products that make your life easier. Our products will help you realize the value of magnets and their many uses!