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sales@tujinmagnet.com
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+86-18858010843
Octagonal Magnets with Hole is a unique and powerful magnet product. Its shape is a regular octagon with a circular hole in the middle. This design not only gives the magnet a unique appearance, but also increases its practicality and flexibility. This magnet is made of high-quality magnetic materials, ensuring its strong magnetic performance and stable magnetic properties.
Shape and size:
Octagonal Magnets with Hole is a regular octagon with smooth and equilateral sides, which makes the magnet more visually balanced and beautiful. The size of the magnet is moderate, neither too small to be difficult to handle nor too large to be inconvenient to carry. Its diameter and thickness are carefully designed to meet the needs of various application scenarios.
Hole design:
Octagonal Magnets with Hole has a circular hole in the middle. This design not only increases the practicality of the magnet, such as being able to hang it in the desired position by rope, hook or other fixing device, but also can be used as an effective means to fix or connect other objects. The size and position of the hole are precisely calculated to ensure that the practical value of the magnet is maximized without affecting the overall performance of the magnet.
High-precision manufacturing
Dimensional accuracy: Octagonal Magnets with Hole undergoes precision machining and quality control during the manufacturing process to ensure high dimensional accuracy. This high accuracy is not only reflected in the overall size of the magnet, but also in the diameter and position accuracy of the hole.
High-performance magnetic materials
High magnetic energy product: Octagonal Magnets with Hole uses high-performance magnetic materials such as neodymium iron boron (NdFeB), which have extremely high magnetic energy products, thus ensuring the strong magnetic performance of the magnet.
High remanence: Remanence is the magnetic strength that a magnet can still maintain after the external magnetic field is removed. The high remanence value of Octagonal Magnets with Hole means that it can still maintain strong magnetism after the external magnetic field is removed, effectively fixing and attracting metal objects.
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 |
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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 |
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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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