37.5 O.R. x 33.5 I.R. x 25mm x 90 degrees N42 Neodymium Arc Magnet, North x4. High-performance Neodymium (N42) arc magnet available with either pole on the inner radius. Grade: N42. Four of these north arc magnets with four of the south polarity version are required to create a 360o 8-pole ring.
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