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SuperMagnetMan Neodymium Ring Magnet.  Used as medical magnets, motor magnets, sensor magnets, consumer electronics magnets.  These ring magnets are strong rare earth neodymium magnets also used as automotive magnets.

 0.157" (4mm) OD x 0.039" (1mm) ID x 0.118" (3mm) thick, N40 Rare Earth Neodymium Ring Magnet, magnetized through thickness. Nickel Plated. 

Minimum Order Quantity (MOQ) = 10 pcs

Neodymium ring magnets are great for use as medical magnets, sensor magnets, motor magnets, consumer electronics magnets, holding magnets and speaker magnets. The "donut hole" shape allows for the magnet to fit on a post to secure it in place.

Ring Magnets can be custom manufactured in different ways so that they can be magnetized in a specific direction.  Below is an overview of the different direction of magnetization options, however, the direction of magnetization can only be set during the manufacturing process and cannot be changed once the magnet is made.

Through the Thickness:  Ring magnets where a magnetic field travels from the ID of the ring magnet to the OD of the ring magnet.

 Through the Diameter:  Ring magnets where a magnetic field flows from the OD of the “north pole” to the OD of the “south pole”.  The ID of the ring magnet will have a magnetic field that is straight and crosses uniformly across the ID.

Radially Magnetized:  Radially magnetized ring magnets have the magnetic poles on the OD / ID instead of the face.  Radial magnets are made as a single piece or in multiple pieces depending upon the size of the magnet.  A list of radial rings is available under our Radial Ring magnet section.

Multi-Pole Magnetization on the Face:  If a ring magnet is large enough it can be magnetized with multiple poles on the face in a North / South configuration.  An example of a multi-pole ring is our part number R1050

SM Magnetics, the engineering and manufacturing sister company of SuperMagnetMan, has been assisting Corporate customers for many years with their custom ring magnet and magnetic assembly applications.

SM Magnetics works with Corporate customers to optimize their design and then manufacture the specific ring magnet or magnetic assembly to meet the required spec.  SM Magnetics has their own ISO certified factories and controls the entire manufacturing process. For assistance from a technical representative at SM Magnetics, click here for the contact info.

For a list of neodymium magnet materials and their characteristics, visit our Neodymium Magnet Table section.  Use care and caution when handling neodymium magnets, as outlined in our Magnet Safety section.


Regular price $0.69
Inside Diameter0.039" (1mm)
Max Working Temp80°C
Outside Diameter0.157" (4mm)
StrengthNeodymium 40
Thickness0.118 (3mm)
Direction of Magnetism Through length

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