Neodymium Ring MagnetsNdFeB Ring MagnetsNdFeB ring magnets are sometimes also known as discs with central holes.  The NdFeB Rings Magnets exits in two styles – 'pure' rings and 'countersunk' rings. The holes are centrally located.  The countersunk ring allows for the magnet to be screwed onto another item such that the screw is flush with the magnet end face. The countersink is only on one side of the ring magnet so the A version has the countersunk end as a North Pole and the B version has the countersunk end as a South Pole. If the countersunk ring is to clamp onto ferromagnetic material then either the A or B version can be used. If two rings are to attract to each other such that the countersunk faces are attracted, one ring has to be an A version and the other a B version (unlike Poles attract).  Due to their shape, the ring magnets have a higher permeance coefficient than a same-sized disc magnet. This means they can resist demagnetization better, making them ideal for repulsive applications.  We can produce the NdFeB circular rod magnets in different sizes, different grades (strengths and temperature ratings), different coatings/finishes and in axial and diametric magnetization as part of our custom magnet  service.  Buyer’s GuideIn order to quote you the best price, please provide us the following informations.ShapeBlock/Rectangle/SquareDisc/Round/CylinderRing/CountersunkDimensionL (?) x W(? ) xT(?)D(?) x T(?)OD(?) x ID(?) x T(?)For other shapes,please tell more in details or drawing would be much appreciated.CoatingZn,Nickel,Ni-Cu-Ni,Epoxy,Au,Silver or other ?Working TemperatureNormal or High temperature ?Working Temperature Grade          Max. Operating TemperatureN35-N52        80°C (176°F)N35M- N50M     100°C (212°F)N35H-N48H      120°C (248°F)N35SH-N45SH    150°C (302°F)N28UH-N40UH    180°C (356°F)N28EH-N38EH    200°C (392°F)N28AH-N35AH    220°C (428°F)DescriptionSintered Neodymium Strong MagnetMaterialNeodymium-Iron-BoronWorking Temperature GradeMax. Operating TemperatureN35-N5280°C (176°F)N35M- N50M100°C (212°F)N35H-N48H120°C (248°F)N35SH-N45SH150°C (302°F)N28UH-N40UH180°C (356°F)N28EH-N38EH200°C (392°F)N28AH-N35AH220°C (428°F)Magnet ShapeDisc, Cylinder, Block, Ring, Countersunk, Segment, Trapezoid, Irregular shapes and more. Customized shapes for Sintered Neodymium Strong Magnets are available.Magnet CoatingNi-Cu-Ni, Nickel, Zn, Gold, Silver, Copper, Epoxy, Phosphating, Chemical, PTFE, Parylene Everlube, Passivation and more.Magnetization Directiona. Thickness Magnetized b. Axially Magnetized c. Diametrally Magnetized d. Multi-poles magnetized e. Radial Magnetized f. Customized specific requirements magnetizedTechnology AdvantageDepending on advanced R&D center, Quality control team and professional machining  technicians, we can surpass our competitors in the stability of quality and  superiority of property.Delivery TimeThe lead time around 10-25daysPayment TermsL/C,T/T,Paypal, ESCROW, Western UnionApplicationSintered Neodymium Strong Magnets are widely used in many fields, such as motors,  sensors, microphones, wind turbines, wind generators, VCMs in hard disk drives,printer,  switchboard, loudspeakers, magnetic separation, magnetic hooks,magnetic holder,  magnetic chuck, common daily use, and so on.