Features: Reliable hardware accessories: The round magnet with bolt is exquisite in workmanship, not easy to rust, wear or break, which can be applied to different use scenarios such as automobiles, tripod heads, lighting and shelves, automatic equipment and other machines. Warm notes: Please use neodymium magnets in an environment below 176 degrees Fahrenheit, otherwise the magnetism will decrease. And, please use them on the flat surface, uneven surface or curved surface will affect the attraction of the magnets. Specifications: Main material: Ndfeb magnets, A3 steel and rubber layer Color: as shown in the picture Size: approx. 1.69 inches in diameter Package includes: 16 Packs of rubber coated neodymium magnets Notes: Manual measurement, please allow slight errors on size. The color may exist slight difference due to different screen displays. Small parts included, please keep away from children in case of choking risk.