20mm countersunk magnet

N38 Grade Down Sinking Hole Magnet 20 x 3 Middle hole 8mm

At first glance, do you think this is an ordinary ring magnet? In fact, it is a sinking ring neodymium magnet. The performance is N38 grade. The specific size is 20mm in diameter, 3mm in thickness, 8mm in the middle hole, and magnetized in thickness. is its schematic diagram....