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MP 40x10.4/5.5x5 / N38 - ring magnet

ring magnet

Catalog no 030249

GTIN/EAN: 5906301812258

5.00
Load capacity 9.47 kg / 92.86 N Magnetic Induction 150.36 mT / 1504 Gs
Diameter
40 mm [±0,1 mm]
internal diameter Ø
10.4/5.5 mm [±0,1 mm]
Height
5 mm [±0,1 mm]
Weight
46.23 g
Magnetization Direction
↑ axial
Coating
[NiCuNi] Nickel

How we measure these parameters — certificates and measurements

see technical data »

21.95 zł net / pcs

27.00 zł with VAT (23% VAT) / pcs

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Frequently asked questions

What is the hole in a ring magnet for?
For mounting on a screw or a shaft. The bore may be cylindrical or countersunk for a screw head. The hole removes magnet volume, so a ring holds less than a disc of the same outside diameter.
What is the polarisation?
Axial as standard — poles on the flat faces of the ring. Diametrical polarisation is made to order.
What sizes are available?
Outside diameter from 5 to 62 mm from stock. To order up to 200 mm outside diameter, 180 mm bore and 40 mm height, with a lead time of 25–35 days.

Guides from the knowledge base

Engineering report for this magnet

Full PDF analysis: pull and shear force, effect of distance, temperature and plate thickness, safety distances and the demagnetization curve.

PDF report Calculator
Want to talk magnets?

Call us now +48 888 99 98 98 alternatively let us know using contact form the contact section.
Specifications and structure of a neodymium magnet can be estimated using our power calculator.

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Technical data of the product - MP 40x10.4/5.5x5 / N38 - ring magnet

Specification / characteristics - MP 40x10.4/5.5x5 / N38 - ring magnet

properties
properties values
Cat. no. 030249
GTIN/EAN 5906301812258
Production/Distribution Dhit sp. z o.o.
ul. Zielona 14 05-850 Ożarów Mazowiecki PL
Country of origin Poland / China / Germany
Customs code 85059029
Diameter 40 mm [±0,1 mm]
internal diameter Ø 10.4/5.5 mm [±0,1 mm]
Height 5 mm [±0,1 mm]
Weight 46.23 g
Magnetization Direction ↑ axial
Load capacity ~ ? 9.47 kg / 92.86 N
Magnetic Induction ~ ? 150.36 mT / 1504 Gs
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 40x10.4/5.5x5 / N38 - ring magnet
properties values units
Remanence Br ? 12.2-12.6 kGs
Remanence Br ? 1220-1260 mT
Coercivity bHc ? 10.8-11.5 kOe
Coercivity bHc ? 860-915 kA/m
Intrinsic coercivity iHc ≥ 12 kOe
Intrinsic coercivity iHc ≥ 955 kA/m
Energy product BHmax ? 36-38 BH max MGOe
Energy product BHmax ? 287-303 BH max KJ/m
Maximum working temperature ? ≤ 80 °C

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C
properties values units
Vickers hardness ≥550 Hv
Density ≥7.4 g/cm3
Curie Temperature TC 310 °C
Curie Temperature TF 590 °F
Specific resistance 150 μΩ⋅cm
Bending strength 250 MPa
Compressive strength 1000~1100 MPa
Thermal expansion parallel (∥) to orientation (M) (3-4) x 10-6 °C-1
Thermal expansion perpendicular (⊥) to orientation (M) -(1-3) x 10-6 °C-1
Young's modulus 1.7 x 104 kg/mm²

Physical simulation of the assembly - report

Presented information constitute the result of a physical analysis. Results are based on models for the material Nd2Fe14B. Actual parameters might slightly differ. Use these data as a supplementary guide when designing systems.

Table 1: Static pull force (pull vs gap) - characteristics
MP 40x10.4/5.5x5 / N38

Distance (mm) Induction (Gauss) / mT Pull Force (kg/lbs/g/N) Risk Status
0 mm 1289 Gs
128.9 mT
 9.47 kg / 20.88 lbs
9470.0 g / 92.9 N
 warning
1 mm 1265 Gs
126.5 mT
 9.12 kg / 20.11 lbs
9120.9 g / 89.5 N
 warning
2 mm 1232 Gs
123.2 mT
 8.66 kg / 19.10 lbs
8662.7 g / 85.0 N
 warning
3 mm 1193 Gs
119.3 mT
 8.12 kg / 17.90 lbs
8121.3 g / 79.7 N
 warning
5 mm 1099 Gs
109.9 mT
 6.89 kg / 15.18 lbs
6887.8 g / 67.6 N
 warning
10 mm 825 Gs
82.5 mT
 3.88 kg / 8.56 lbs
3882.0 g / 38.1 N
 warning
15 mm 580 Gs
58.0 mT
 1.92 kg / 4.22 lbs
1915.5 g / 18.8 N
 weak grip
20 mm 399 Gs
39.9 mT
 0.91 kg / 2.00 lbs
908.3 g / 8.9 N
 weak grip
30 mm 195 Gs
19.5 mT
 0.22 kg / 0.48 lbs
217.6 g / 2.1 N
 weak grip
50 mm 61 Gs
6.1 mT
 0.02 kg / 0.05 lbs
21.0 g / 0.2 N
 weak grip
Magnetic force drops drastically per each millimeter of distance. Note that even a very thin break (e.g., dirt, paint, dust) strongly weakens the grip. Magnetic products operate strongest at the point of direct contact; distance weakens the power. Notice how quickly the load capacity fall, when the magnet does not touch directly to the steel surface. When calculating the mounting, discard redundant distances.

Table 2: Shear force (wall)
MP 40x10.4/5.5x5 / N38

Distance (mm) Friction coefficient Pull Force (kg/lbs/g/N)
0 mm Stal (~0.2) 1.89 kg / 4.18 lbs
1894.0 g / 18.6 N
1 mm Stal (~0.2) 1.82 kg / 4.02 lbs
1824.0 g / 17.9 N
2 mm Stal (~0.2) 1.73 kg / 3.82 lbs
1732.0 g / 17.0 N
3 mm Stal (~0.2) 1.62 kg / 3.58 lbs
1624.0 g / 15.9 N
5 mm Stal (~0.2) 1.38 kg / 3.04 lbs
1378.0 g / 13.5 N
10 mm Stal (~0.2) 0.78 kg / 1.71 lbs
776.0 g / 7.6 N
15 mm Stal (~0.2) 0.38 kg / 0.85 lbs
384.0 g / 3.8 N
20 mm Stal (~0.2) 0.18 kg / 0.40 lbs
182.0 g / 1.8 N
30 mm Stal (~0.2) 0.04 kg / 0.10 lbs
44.0 g / 0.4 N
50 mm Stal (~0.2) 0.00 kg / 0.01 lbs
4.0 g / 0.0 N
This section calculates the estimated weight limit necessary to start the shifting of the magnet down on a vertical metal surface (assuming typical friction). This value is a function of the gap size between the magnet and the surface.

Table 3: Wall mounting (shearing) - vertical pull
MP 40x10.4/5.5x5 / N38

Surface type Friction coefficient / % Mocy Max load (kg/lbs/g/N)
Raw steel
µ = 0.3 30% Nominalnej Siły
2.84 kg / 6.26 lbs
2841.0 g / 27.9 N
Painted steel (standard)
µ = 0.2 20% Nominalnej Siły
1.89 kg / 4.18 lbs
1894.0 g / 18.6 N
Oily/slippery steel
µ = 0.1 10% Nominalnej Siły
0.95 kg / 2.09 lbs
947.0 g / 9.3 N
Magnet with anti-slip rubber
µ = 0.5 50% Nominalnej Siły
4.74 kg / 10.44 lbs
4735.0 g / 46.5 N
When hanging a holder on a vertical surface (e.g., a car body), it will only hold barely about 20%-30% of nominal attraction strength. Gravitational force as well as a low friction coefficient mean that magnets slip faster than they detach. Planning a vertical fastening? Note that the shear force is significantly lower than the maximum static pull force. On a slippery surface, the element will slide down under a significantly smaller load. Utilizing a rubberized coating can effectively raise the stability.

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 40x10.4/5.5x5 / N38

Steel thickness (mm) % power Real pull force (kg/lbs/g/N)
0.5 mm
10%
 0.95 kg / 2.09 lbs
947.0 g / 9.3 N
1 mm
25%
 2.37 kg / 5.22 lbs
2367.5 g / 23.2 N
2 mm
50%
 4.74 kg / 10.44 lbs
4735.0 g / 46.5 N
3 mm
75%
 7.10 kg / 15.66 lbs
7102.5 g / 69.7 N
5 mm
100%
 9.47 kg / 20.88 lbs
9470.0 g / 92.9 N
10 mm
100%
 9.47 kg / 20.88 lbs
9470.0 g / 92.9 N
11 mm
100%
 9.47 kg / 20.88 lbs
9470.0 g / 92.9 N
12 mm
100%
 9.47 kg / 20.88 lbs
9470.0 g / 92.9 N
A too thin steel cannot take in the entire magnetic field, which squanders power of the holder. If you install a neodymium to a thin surface, the magnetism will pass right through and the attraction force will be weaker. To utilize 100% of this neodymium's power, you require a sufficiently solid element of steel. The saturation effect causes that on sheet metal structures (e.g., thin profiles), the holder shows lower pull force. We recommend selecting the steel dimension according to the table below.

Table 5: Thermal stability (stability) - thermal limit
MP 40x10.4/5.5x5 / N38

Ambient temp. (°C) Power loss Remaining pull (kg/lbs/g/N) Status
20 °C 0.0% 9.47 kg / 20.88 lbs
9470.0 g / 92.9 N
 OK
40 °C -2.2% 9.26 kg / 20.42 lbs
9261.7 g / 90.9 N
 OK
60 °C -4.4% 9.05 kg / 19.96 lbs
9053.3 g / 88.8 N
80 °C -6.6% 8.84 kg / 19.50 lbs
8845.0 g / 86.8 N
100 °C -28.8% 6.74 kg / 14.86 lbs
6742.6 g / 66.1 N
Ordinary NdFeB products lose power above the temperature limit. Avoid high temperatures – excessive heat can irreversibly damage this magnet. As the temperature rises, the neodymium's capacity temporarily drops. Do not use this magnet close to ovens higher than its safe range. Ignoring the limit will lead to irreversible degradation of magnetism.
*Engineering note: Heat tolerance is determined by both grade, but also on the magnet's shape. Thin magnets (low permeance coefficient) are more susceptible to demagnetization under lower heat stress than long magnets. Warning indicator in the table points to a risk of irreversible loss for this particular item.

Table 6: Two magnets (attraction) - field collision
MP 40x10.4/5.5x5 / N38

Gap (mm) Attraction (kg/lbs) (N-S) Shear Force (kg/lbs/g/N) Repulsion (kg/lbs) (N-N)
0 mm 10.73 kg / 23.65 lbs
2 424 Gs
1.61 kg / 3.55 lbs
1609 g / 15.8 N
 N/A
1 mm 10.55 kg / 23.25 lbs
2 555 Gs
1.58 kg / 3.49 lbs
1582 g / 15.5 N
 9.49 kg / 20.93 lbs
~0 Gs
2 mm 10.33 kg / 22.78 lbs
2 529 Gs
1.55 kg / 3.42 lbs
1550 g / 15.2 N
 9.30 kg / 20.50 lbs
~0 Gs
3 mm 10.09 kg / 22.23 lbs
2 499 Gs
1.51 kg / 3.34 lbs
1513 g / 14.8 N
 9.08 kg / 20.01 lbs
~0 Gs
5 mm 9.52 kg / 20.98 lbs
2 427 Gs
1.43 kg / 3.15 lbs
1427 g / 14.0 N
 8.56 kg / 18.88 lbs
~0 Gs
10 mm 7.80 kg / 17.20 lbs
2 198 Gs
1.17 kg / 2.58 lbs
1170 g / 11.5 N
 7.02 kg / 15.48 lbs
~0 Gs
20 mm 4.40 kg / 9.69 lbs
1 650 Gs
0.66 kg / 1.45 lbs
660 g / 6.5 N
 3.96 kg / 8.72 lbs
~0 Gs
50 mm 0.49 kg / 1.09 lbs
553 Gs
0.07 kg / 0.16 lbs
74 g / 0.7 N
 0.44 kg / 0.98 lbs
~0 Gs
60 mm 0.25 kg / 0.54 lbs
391 Gs
0.04 kg / 0.08 lbs
37 g / 0.4 N
 0.22 kg / 0.49 lbs
~0 Gs
70 mm 0.13 kg / 0.28 lbs
282 Gs
0.02 kg / 0.04 lbs
19 g / 0.2 N
 0.12 kg / 0.26 lbs
~0 Gs
80 mm 0.07 kg / 0.15 lbs
209 Gs
0.01 kg / 0.02 lbs
11 g / 0.1 N
 0.06 kg / 0.14 lbs
~0 Gs
90 mm 0.04 kg / 0.09 lbs
158 Gs
0.01 kg / 0.01 lbs
6 g / 0.1 N
 0.04 kg / 0.08 lbs
~0 Gs
100 mm 0.02 kg / 0.05 lbs
121 Gs
0.00 kg / 0.01 lbs
4 g / 0.0 N
 0.02 kg / 0.05 lbs
~0 Gs
Two strong neodymiums attract each other from a much further distance than a magnet and steel combination. Such a system of magnet-to-magnet produces a massive flux and a further horizon of action. Planning to create a powerful holder? Utilize two neodymiums instead of one magnet and a steel. Remember that when bringing together two magnets, the collision energy is huge. The repulsion force is a bit weaker than the attraction, but still large.
*Flux density between like poles reaches ~0 Gs in the exact middle between the magnets (resulting from vector opposition).
Note: Results demonstrate friction force of two same neodymium magnets (friction ~0.15 for Ni-Ni plating).

Table 7: Hazards (implants) - precautionary measures
MP 40x10.4/5.5x5 / N38

Object / Device Limit (Gauss) / mT Safe distance
Pacemaker 5 Gs (0.5 mT) 12.5 cm
Hearing aid 10 Gs (1.0 mT) 10.0 cm
Mechanical watch 20 Gs (2.0 mT) 8.0 cm
Phone / Smartphone 40 Gs (4.0 mT) 6.0 cm
Car key 50 Gs (5.0 mT) 5.5 cm
Payment card 400 Gs (40.0 mT) 2.0 cm
HDD hard drive 600 Gs (60.0 mT) 1.5 cm
Powerful magnet radiation poses a large risk to electronic devices as well as pacemakers. These NdFeB products produce a flux that disrupts operation of sensitive medical devices. Be aware: the unseen radiation penetrates the body and plastic. Exceptional care must be exercised by people with hearing aids and drug dispensers. Influence will be felt by: mechanical watches, remotes, membranes, and displays. Do not place the magnet near cards, hard drives, or precise measuring instruments.

Table 8: Dynamics (cracking risk) - warning
MP 40x10.4/5.5x5 / N38

Start from (mm) Speed (km/h) Energy (J) Predicted outcome
10 mm 19.38 km/h
(5.38 m/s)
 0.67 J
30 mm 22.72 km/h
(6.31 m/s)
 0.92 J
50 mm 22.91 km/h
(6.36 m/s)
 0.94 J
100 mm 22.94 km/h
(6.37 m/s)
 0.94 J
Magnetic elements are delicate – a collision with steel can result in shattering. Watch the impact speed – a neodymium left loose becomes dangerous. Kinetic force can trigger coating fragments or painful pinches to fingers. Hold the magnet firmly during bringing near metal so it doesn't hit with great force against the metal. A contact at a velocity of dozens of km/h almost guarantees destruction of the neodymium. Use safety goggles when playing with powerful specimens.

Table 9: Coating parameters (durability)
MP 40x10.4/5.5x5 / N38

Technical parameter Value / Description
Coating type [NiCuNi] Nickel
Layer structure Nickel - Copper - Nickel
Layer thickness 10-20 µm
Salt spray test (SST) ? 24 h
Recommended environment Indoors only (dry)
The following table defines the conditions under which this product can be safely used. Improper coating selection is the most common cause of magnet failure over time.

Table 10: Electrical data (Flux)
MP 40x10.4/5.5x5 / N38

Parameter Value SI Unit / Description
Magnetic Flux 17 767 Mx 177.7 µWb
Pc Coefficient 0.17 Low (Flat)
Total magnetic flux emitted by the magnet pole. Key data in coil applications and motors. The Pc coefficient defines the working geometry.

Table 11: Underwater work (magnet fishing)
MP 40x10.4/5.5x5 / N38

Environment Effective steel pull Effect
Air (land) 9.47 kg Standard
Water (riverbed) 10.84 kg
(+1.37 kg buoyancy gain)
+14.5%
Rust risk: This magnet has a standard nickel coating. After use in water, it must be dried and maintained immediately, otherwise it will rust!
The magnetic field penetrates through water without any losses. Note: for permanent underwater work, we recommend magnets with an anti-corrosive (epoxy) coating.

1. Vertical hold

*Caution: On a vertical wall, the magnet holds merely approx. 20-30% of its max power.

2. Steel saturation

*Thin metal sheet (e.g. computer case) significantly weakens the holding force.

3. Power loss vs temp

*For N38 material, the critical limit is 80°C.

4. Demagnetization curve and operating point (B-H)

chart generated for the permeance coefficient Pc (Permeance Coefficient) = 0.17

This simulation demonstrates the magnetic stability of the selected magnet under specific geometric conditions. The solid red line represents the demagnetization curve (material potential), while the dashed blue line is the load line based on the magnet's geometry. The Pc (Permeance Coefficient), also known as the load line slope, is a dimensionless value that describes the relationship between the magnet's shape and its magnetic stability. The intersection of these two lines (the black dot) is the operating point — it determines the actual magnetic flux density generated by the magnet in this specific configuration. A higher Pc value means the magnet is more 'slender' (tall relative to its area), resulting in a higher operating point and better resistance to irreversible demagnetization caused by external fields or temperature. A value of 0.42 is relatively low (typical for flat magnets), meaning the operating point is closer to the 'knee' of the curve — caution is advised when operating at temperatures near the maximum limit to avoid strength loss.

Technical and environmental data

Material specification

iron (Fe) 64% – 68%
neodymium (Nd) 29% – 32%
boron (B) 1.1% – 1.2%
dysprosium (Dy) 0.5% – 2.0%
coating (Ni-Cu-Ni) < 0.05%

Environmental data

recyclability (EoL) 100%
recycled raw materials ~10% (pre-cons)
carbon footprint low / zredukowany
waste code (EWC) 16 02 16
Safety card (GPSR)
responsible entity
Dhit sp. z o.o.
ul. Kościuszki 6A, 05-850 Ożarów Mazowiecki
tel: +48 22 499 98 98 | e-mail: bok@dhit.pl
batch number/type
id: 030249-2026
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It is ideally suited for places where solid attachment of the magnet to the substrate is required without the risk of detachment. Thanks to the hole (often for a screw), this model enables quick installation to wood, wall, plastic, or metal. This product with a force of 9.47 kg works great as a cabinet closure, speaker holder, or spacer element in devices.
This material behaves more like porcelain than steel, so it doesn't forgive mistakes during mounting. One turn too many can destroy the magnet, so do it slowly. The flat screw head should evenly press the magnet. Remember: cracking during assembly results from material properties, not a product defect.
Moisture can penetrate micro-cracks in the coating and cause oxidation of the magnet. In the place of the mounting hole, the coating is thinner and can be damaged when tightening the screw, which will become a corrosion focus. This product is dedicated for inside building use. For outdoor applications, we recommend choosing rubberized holders or additional protection with varnish.
A screw or bolt with a thread diameter smaller than 10.4/5.5 mm fits this model. If the magnet does not have a chamfer (cone), we recommend using a screw with a flat or cylindrical head, or possibly using a washer. Aesthetic mounting requires selecting the appropriate head size.
The presented product is a ring magnet with dimensions Ø40 mm (outer diameter) and height 5 mm. The key parameter here is the holding force amounting to approximately 9.47 kg (force ~92.86 N). The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 10.4/5.5 mm.
These magnets are magnetized axially (through the thickness), which means one flat side is the N pole and the other is S. If you want two such magnets screwed with cones facing each other (faces) to attract, you must connect them with opposite poles (N to S). When ordering a larger quantity, magnets are usually packed in stacks, where they are already naturally paired.

Advantages as well as disadvantages of neodymium magnets.

Benefits

In addition to their pulling strength, neodymium magnets provide the following advantages:
  • Their magnetic field is maintained, and after approximately 10 years it decreases only by ~1% (according to research),
  • Magnets very well defend themselves against demagnetization caused by external fields,
  • By covering with a smooth coating of silver, the element gains an professional look,
  • The surface of neodymium magnets generates a unique magnetic field – this is one of their assets,
  • Thanks to resistance to high temperature, they can operate (depending on the form) even at temperatures up to 230°C and higher...
  • Possibility of accurate modeling and modifying to complex needs,
  • Wide application in electronics industry – they are commonly used in hard drives, electric drive systems, medical devices, also multitasking production systems.
  • Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in compact dimensions, which enables their usage in miniature devices

Weaknesses

Drawbacks and weaknesses of neodymium magnets and ways of using them
  • At very strong impacts they can break, therefore we advise placing them in special holders. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
  • When exposed to high temperature, neodymium magnets suffer a drop in power. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
  • Magnets exposed to a humid environment can rust. Therefore while using outdoors, we suggest using water-impermeable magnets made of rubber, plastic or other material resistant to moisture
  • Due to limitations in creating threads and complex shapes in magnets, we recommend using a housing - magnetic holder.
  • Potential hazard to health – tiny shards of magnets are risky, when accidentally swallowed, which becomes key in the context of child safety. It is also worth noting that small elements of these products are able to complicate diagnosis medical after entering the body.
  • High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which can limit application in large quantities

Holding force characteristics

Optimal lifting capacity of a neodymium magnet – what contributes to it?

The specified lifting capacity concerns the peak performance, obtained under ideal test conditions, specifically:
  • using a sheet made of mild steel, functioning as a circuit closing element
  • whose thickness equals approx. 10 mm
  • characterized by smoothness
  • without the slightest air gap between the magnet and steel
  • during detachment in a direction vertical to the plane
  • at ambient temperature approx. 20 degrees Celsius

Determinants of practical lifting force of a magnet

Effective lifting capacity impacted by specific conditions, mainly (from most important):
  • Distance – the presence of foreign body (rust, tape, gap) interrupts the magnetic circuit, which reduces capacity rapidly (even by 50% at 0.5 mm).
  • Direction of force – maximum parameter is obtained only during pulling at a 90° angle. The shear force of the magnet along the plate is typically many times smaller (approx. 1/5 of the lifting capacity).
  • Wall thickness – thin material does not allow full use of the magnet. Magnetic flux penetrates through instead of generating force.
  • Steel grade – ideal substrate is high-permeability steel. Cast iron may attract less.
  • Base smoothness – the smoother and more polished the plate, the better the adhesion and stronger the hold. Roughness creates an air distance.
  • Thermal factor – hot environment reduces pulling force. Too high temperature can permanently damage the magnet.

Lifting capacity was assessed with the use of a smooth steel plate of suitable thickness (min. 20 mm), under vertically applied force, in contrast under attempts to slide the magnet the load capacity is reduced by as much as 5 times. Moreover, even a small distance between the magnet and the plate reduces the holding force.

Precautions when working with NdFeB magnets
Impact on smartphones

An intense magnetic field disrupts the functioning of magnetometers in phones and navigation systems. Keep magnets near a smartphone to prevent damaging the sensors.

Pacemakers

For implant holders: Strong magnetic fields disrupt medical devices. Keep at least 30 cm distance or ask another person to work with the magnets.

No play value

These products are not intended for children. Swallowing a few magnets can lead to them connecting inside the digestive tract, which poses a direct threat to life and necessitates immediate surgery.

Warning for allergy sufferers

It is widely known that the nickel plating (standard magnet coating) is a strong allergen. For allergy sufferers, avoid touching magnets with bare hands and opt for encased magnets.

Permanent damage

Standard neodymium magnets (N-type) undergo demagnetization when the temperature exceeds 80°C. The loss of strength is permanent.

Beware of splinters

Neodymium magnets are sintered ceramics, meaning they are fragile like glass. Collision of two magnets leads to them cracking into small pieces.

Data carriers

Do not bring magnets close to a purse, computer, or TV. The magnetic field can destroy these devices and wipe information from cards.

Do not underestimate power

Handle magnets with awareness. Their huge power can shock even experienced users. Plan your moves and respect their power.

Pinching danger

Pinching hazard: The pulling power is so immense that it can cause blood blisters, crushing, and even bone fractures. Use thick gloves.

Dust explosion hazard

Fire hazard: Neodymium dust is explosive. Do not process magnets without safety gear as this risks ignition.

Danger! Looking for details? Read our article: Why are neodymium magnets dangerous?