Ring Shape Neodymium magnet for Speakers The lagest size can be ... Ag, Ni-Au, etc. Applications: Wind Power Generators, Motor Parts, MRI/Nuclear Magnetic Resonance (NMR), Magnetic Separators, ... 1500C (depending on grade and permeance coefficient magnet is operating at) The highest working temperature ... 25KOeShape Available: blocks, bars, discs, rings, arc segments, etc.Grade Available:N35 to N53,N,M ...