This is a bonded ring magnet with a multi-pole magnetization through the inner diameter, there are 4 magnetic poles, made by the courage magnet manufacturer, outer diameter of the magnetic ring is 28mm, hole is 24.8mm, height is 8.5mm, the surface coating is black electrophoresis, the surface magnetic intensity is about 1500 Gauss, if you want to get the price, please contact us through the inquiry. We have a lot more to offer near the specifications.
Radial inner diameter 4 pole magnetized ring magnet physical sample picture

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