This product is a super-large diameter ring magnet, it can also be called a death magnet, NdFeb material, outer diameter of more than 7 inches (190mm), the material is rare earth NdFeb, mainly used in heavy industry, large mechanical equipment, experiments and other purposes, the use of extra care.
Other large ring rare earth magnets;
10cm diameter strong large neodymium ring magnets 100x85x3.5mm
30mm Thick Large Neodymium Round Magnet with Hole Diameter 200mm