Neodymium magnets and Stainless Steel,allowing you to add storage without drilling holes into wall or using the nails 2. They are ideal for storaging anything from tools to accessories, coat, bag and so on. 3. 6-Pack of metal magnetic hooks are made with Black Coating. 4. You can use the portable hooks to hanger the broom, the aprons, the cup, the pot, the towel, the clothes, utensils,the oven. 5. You can use the Tohoer magnetic hooks on shelves, sink, desk, shed, garden, bars. Place in different locations to hang keys, accessories and so on. WARNING 1.Not for Children 2.Keep away from electronic equipment,such as smartphone,credit card etc. 3.Powerful magnets could hurt your fingers.Please wear a pair of gloves to handle them for your safety. 4.The Maximum Working temperature of neodymium magnets is 176 F (80 C)