This is a type of ring magnet with an outer diameter of 120mm, which belongs to the large size magnet series. The material is strong magnetic Ndfeb, the inner hole (straight hole) size is 70mm, the height is 7mm, the surface coating is nickel, magnetization through the thickness direction, the magnetic force is strong, the tension is not tested, the magnetic strength of the surface is about 3620 Gauss...