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sales@tujinmagnet.com
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+86-18858010843
Unique countersunk design:
Unlike other ring magnets, Permanent Powerful Ring Magnet with Countersunk comes with a unique countersunk design. This design not only gives the magnet a unique look, but more importantly, it provides users with more installation options. Users can fix the magnet in the desired position with screws or other fasteners to achieve a more stable connection and installation.
This design makes the application of magnets in electronic equipment, automobile manufacturing and other fields more flexible and convenient.
Silver-white color, smooth and shiny:
The surface of the magnet presents a silver-white color, smooth and shiny, which not only enhances the beauty of the product, but also makes the magnet show elegance and refinement in various application scenarios. At the same time, the smooth surface is also easy to clean and maintain, extending the service life of the product.
Moderate size, easy to use:
The size of this magnet is moderate, neither too large to make it difficult to install, nor too small to affect the magnetic effect. Its ring design makes the magnet more convenient to use, and it can be easily put on the required items or fixed through the countersunk. In addition, we also provide a variety of specifications and sizes for users to choose from to meet the needs of different application scenarios.
Permanent Powerful Magnet:
Permanent Powerful Ring Magnet with Countersunk is made of high-quality magnetic material, Neodymium Iron Boron (NdFeB), to ensure permanent strong magnetism. Neodymium Iron Boron has the characteristics of high magnetic energy product, high remanence and high coercive force, which enables this magnet to maintain stable magnetic performance in various harsh environments. Whether it is adsorbing heavy objects or achieving precise magnetic connection, this magnet can easily cope with it and provide reliable protection for your application.
Corrosion and oxidation resistance:
Our magnets have undergone special anti-corrosion treatment and have excellent corrosion resistance and oxidation resistance. Even when used in humid or corrosive environments, they can maintain long-term magnetic performance and stable performance. This makes the application of magnets in outdoor equipment, marine engineering and other fields more reliable.
Products show

Surface Coating & Corrosoin Resistance
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| Nickel(Ni-Cu-Ni) | Zinc(Zn) | Black Epoxy | Gold |
| Type | Color | Plating Thickness | Working Temperature |
Advantage & Suitable | Salt Spray Resistance | |||||
| Nickel(NiCuNi) | silver | 20-30 um | ≤200 | high oxidation resistance, good glossiness, stable performance, long service life | > 72 hrs | |||||
| Zinc (Zn) | blue white | 10-20 um | ≤160 | suitable for low requirements for surface appearance & oxidation resistance | > 48 hrs | |||||
| Epoxy | black | 10-30 um | ≤120 | suitable for high anti-corrosion and strict atmospheric environment | > 96 hrs | |||||
| Gold | Gold | 5-30 um | ≤200 | suitable for decoration accessories, gift box etc. | > 24 hrs | |||||
Tolerance

| Standard Product | D.OD | ID | L | W | H |
| <5mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <10mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <20mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <50mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <100mm | ±0.15mm | ±0.15mm | ±0.15mm | ±0.15mm | ±0.15mm |
| >100mm | ±0.2mm | ±0.2mm | ±0.2mm | ±0.2mm | ±0.2mm |
Magnetization Direction
| Disc&Cylinder-through Thickness | Disc&Cylinder-through Diameter | Spheres- through Diameter |
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Poles on the flat surfaces
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Poles on the side surfaces |
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| Block- through Thickness | Block- through Length | Arc- through Diamter |
|
Poles on the larger flat surfaces |
Poles on the smaller flat surfaces |
Poles on outside&inside faces |
| Arc- through Length | Ring- through Surfaces | Ring- through Surfaces |
|
Poles on outside&inside faces |
Planar octupole magnetization |
Planar quadrupole magnetization |
Sintered NdFeB Magnetic Properties
| Grade | Remanence | Coercive Force | Intrinsic Coercivity | Maximum Energy | Working≤ | |||||||
| Br(KG) | Br(T) | Hcb (KOe) |
Hcb (KA/m) |
Hcj (KOe) |
Hcj (KA/m) |
(BH)max(MGOe) | (BH)max (KJ/ m) |
℃ | ||||
| Max | Min | Max | Min | |||||||||
| N35 | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥12 | ≥960 | 37 | 33 | 295 | 263 | N | ≤80 |
| N38 | ≥12.3 | ≥1.23 | ≥10.8 | ≥860 | ≥12 | ≥960 | 39 | 36 | 310 | 287 | ||
| N40 | ≥12.7 | ≥1.27 | ≥11.0 | ≥876 | ≥12 | ≥960 | 41 | 38 | 327 | 302 | ||
| N42 | ≥13.0 | ≥1.30 | ≥11.0 | ≥876 | ≥12 | ≥960 | 43 | 40 | 343 | 320 | ||
| N45 | ≥13.3 | ≥1.33 | ≥11.0 | ≥876 | ≥12 | ≥960 | 46 | 42 | 366 | 335 | ||
| N48 | ≥13.7 | ≥1.37 | ≥10.5 | ≥836 | ≥12 | ≥960 | 49 | 45 | 390 | 358 | ||
| N50 | ≥14.0 | ≥1.40 | ≥10.5 | ≥836 | ≥12 | ≥960 | 51 | 47 | 406 | 374 | ||
| N52 | ≥14.2 | ≥1.42 | ≥10.5 | ≥836 | ≥12 | ≥960 | 53 | 49 | 422 | 390 | ||
| N54 | ≥14.4 | ≥1.44 | ≥10.5 | ≥836 | ≥11 | ≥876 | 55 | 51 | 438 | 406 | ||
| N35M | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥14 | ≥1114 | 37 | 33 | 295 | 263 | M | ≤100 |
| N38M | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥14 | ≥1114 | 39 | 36 | 310 | 287 | ||
| N40M | ≥12.7 | ≥1.27 | ≥11.5 | ≥915 | ≥14 | ≥1114 | 41 | 38 | 327 | 302 | ||
| N42M | ≥13.0 | ≥1.30 | ≥11.8 | ≥939 | ≥14 | ≥1114 | 43 | 40 | 343 | 320 | ||
| N45M | ≥13.3 | ≥1.33 | ≥12.0 | ≥956 | ≥14 | ≥1114 | 46 | 42 | 366 | 335 | ||
| N48M | ≥13.7 | ≥1.37 | ≥12.2 | ≥972 | ≥14 | ≥1114 | 49 | 45 | 390 | 358 | ||
| N50M | ≥14.0 | ≥1.40 | ≥12.5 | ≥995 | ≥14 | ≥1114 | 51 | 47 | 406 | 374 | ||
| N52M | ≥14.2 | ≥1.42 | ≥12.5 | ≥995 | ≥14 | ≥1114 | 53 | 49 | 422 | 390 | ||
| N33H | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥17 | ≥1350 | 35 | 31 | 279 | 247 | H | ≤120 |
| N35H | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥17 | ≥1350 | 37 | 33 | 295 | 263 | ||
| N38H | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥17 | ≥1350 | 39 | 36 | 310 | 287 | ||
| N40H | ≥12.7 | ≥1.27 | ≥11.5 | ≥916 | ≥17 | ≥1350 | 41 | 38 | 327 | 302 | ||
| N42H | ≥13.0 | ≥1.30 | ≥11.8 | ≥940 | ≥17 | ≥1350 | 43 | 40 | 343 | 320 | ||
| N45H | ≥13.3 | ≥1.33 | ≥12.0 | ≥955 | ≥17 | ≥1350 | 46 | 42 | 366 | 335 | ||
| N48H | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥17 | ≥1350 | 49 | 45 | 390 | 358 | ||
| N50H | ≥14 | ≥1.4 | ≥12.5 | ≥995 | ≥17 | ≥1350 | 51 | 47 | 406 | 374 | ||
| N52H | ≥14.3 | ≥1.43 | ≥12.5 | ≥995 | ≥17 | ≥1350 | 53 | 49 | 422 | 390 | ||
| N33SH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥20 | ≥1592 | 35 | 31 | 279 | 247 | SH | ≤150 |
| N35SH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥20 | ≥1592 | 37 | 33 | 295 | 263 | ||
| N38SH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥20 | ≥1592 | 39 | 36 | 310 | 287 | ||
| N40SH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥20 | ≥1592 | 41 | 38 | 327 | 302 | ||
| N42SH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥20 | ≥1592 | 43 | 40 | 343 | 320 | ||
| N45SH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥20 | ≥1592 | 46 | 42 | 366 | 335 | ||
| N48SH | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥20 | ≥1592 | 49 | 45 | 390 | 358 | ||
| N50SH | ≥14 | ≥1.4 | ≥12.5 | ≥995 | ≥20 | ≥1592 | 51 | 47 | 406 | 374 | ||
| N33UH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥25 | ≥1990 | 35 | 31 | 279 | 247 | UH | ≤180 |
| N35UH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥25 | ≥1990 | 37 | 33 | 295 | 263 | ||
| N38UH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥25 | ≥1990 | 39 | 36 | 310 | 287 | ||
| N40UH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥25 | ≥1990 | 41 | 38 | 327 | 302 | ||
| N42UH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥25 | ≥1990 | 43 | 40 | 343 | 320 | ||
| N45UH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥25 | ≥1990 | 46 | 42 | 366 | 335 | ||
| N48UH | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥25 | ≥1990 | 49 | 45 | 390 | 358 | ||
| N28EH | ≥10.4 | ≥1.04 | ≥9.50 | ≥756 | ≥30 | ≥2388 | 30 | 26 | 239 | 207 | EH | ≤200 |
| N30EH | ≥10.8 | ≥1.08 | ≥9.50 | ≥756 | ≥30 | ≥2388 | 32 | 28 | 255 | 223 | ||
| N33EH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥30 | ≥2388 | 35 | 31 | 279 | 247 | ||
| N35EH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥30 | ≥2388 | 37 | 33 | 295 | 263 | ||
| N38EH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥30 | ≥2388 | 39 | 36 | 310 | 287 | ||
| N40EH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥30 | ≥2388 | 41 | 38 | 327 | 302 | ||
| N42EH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥30 | ≥2388 | 43 | 41 | 343 | 320 | ||
| N45EH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥30 | ≥2388 | 46 | 42 | 366 | 335 | ||
| N30TH | ≥10.8 | ≥1.08 | ≥9.50 | ≥756 | ≥35 | ≥2786 | 32 | 28 | 255 | 223 | TH | ≤220 |
| N33TH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥35 | ≥2786 | 35 | 31 | 279 | 247 | ||
| N35TH | ≥11.8 | ≥1.18 | ≥11.0 | ≥876 | ≥35 | ≥2786 | 37 | 33 | 295 | 263 | ||
| N38TH | ≥12.2 | ≥1.22 | ≥11.0 | ≥876 | ≥33 | ≥2627 | 39 | 36 | 310 | 287 | ||
| Remarks: The maximum working temperature depends on the shape, size, and coating of the magnet, the highest working temperature in the table is the test data for standard sample. | ||||||||||||
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