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MW 20x18 / N38 - cylindrical magnet

cylindrical magnet

Catalog no 010040

GTIN/EAN: 5906301810391

Load capacity 13.19 kg / 129.35 N Magnetic Induction 541.64 mT / 5416 Gs
Diameter Ø
20 mm [±0,1 mm]
Height
18 mm [±0,1 mm]
Weight
42.41 g
Magnetization Direction
↑ axial
Coating
[NiCuNi] Nickel

How we measure these parameters — certificates and measurements

see properties »

19.14 zł net / pcs

23.54 zł with VAT (23% VAT) / pcs

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Frequently asked questions

What is the maximum working temperature of a disc magnet?
Standard N-series grades work up to 80 °C. Grades N50, N52 and N54 have a lower limit of 60 °C, because coercivity falls as BHmax rises. Higher temperatures require the H (120 °C), SH (150 °C), UH (180 °C), EH (200 °C) or AH (230 °C) series. Within the working range the magnet loses about 0.11% of its induction per degree, and that loss is reversible.
What is the difference between N38, N42 and N52?
The number after N is the energy product BHmax. Moving from N38 to N52 raises it by several tens of percent, but the real holding force increases by roughly 20%, because force also depends on geometry and on the magnetic circuit. N52 costs about twice as much as N42, so for most mounting work N38–N42 is the best price-to-force ratio.
What is the dimensional tolerance?
±0.1 mm as standard, ±0.05 mm to order. The tolerance is stated next to the dimensions on every product page.

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 of the product - MW 20x18 / N38 - cylindrical magnet

Specification / characteristics - MW 20x18 / N38 - cylindrical magnet

properties
properties values
Cat. no. 010040
GTIN/EAN 5906301810391
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 Ø 20 mm [±0,1 mm]
Height 18 mm [±0,1 mm]
Weight 42.41 g
Magnetization Direction ↑ axial
Load capacity ~ ? 13.19 kg / 129.35 N
Magnetic Induction ~ ? 541.64 mT / 5416 Gs
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±0.1 mm

Magnetic properties of material N38

Specification / characteristics MW 20x18 / N38 - cylindrical 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

Engineering modeling of the magnet - technical parameters

The following values constitute the result of a physical simulation. Results rely on algorithms for the class Nd2Fe14B. Operational conditions might slightly differ. Treat these calculations as a preliminary roadmap when designing systems.

Table 1: Static force (pull vs distance) - power drop
MW 20x18 / N38

Distance (mm) Induction (Gauss) / mT Pull Force (kg/lbs/g/N) Risk Status
0 mm 5414 Gs
541.4 mT
 13.19 kg / 29.08 LBS
13190.0 g / 129.4 N
 critical level
1 mm 4870 Gs
487.0 mT
 10.67 kg / 23.52 LBS
10669.5 g / 104.7 N
 critical level
2 mm 4330 Gs
433.0 mT
 8.43 kg / 18.59 LBS
8434.2 g / 82.7 N
 warning
3 mm 3816 Gs
381.6 mT
 6.55 kg / 14.45 LBS
6552.7 g / 64.3 N
 warning
5 mm 2913 Gs
291.3 mT
 3.82 kg / 8.42 LBS
3818.4 g / 37.5 N
 warning
10 mm 1455 Gs
145.5 mT
 0.95 kg / 2.10 LBS
952.2 g / 9.3 N
 weak grip
15 mm 775 Gs
77.5 mT
 0.27 kg / 0.60 LBS
270.1 g / 2.7 N
 weak grip
20 mm 450 Gs
45.0 mT
 0.09 kg / 0.20 LBS
91.3 g / 0.9 N
 weak grip
30 mm 188 Gs
18.8 mT
 0.02 kg / 0.04 LBS
15.9 g / 0.2 N
 weak grip
50 mm 54 Gs
5.4 mT
 0.00 kg / 0.00 LBS
1.3 g / 0.0 N
 weak grip
Grip strength weakens drastically with every mm of spacing. Keep in mind that every additional insulation layer (e.g., dirt, paint, rust) noticeably diminishes the holding power. Magnetic products operate optimally during direct contact; gap nullifies the power. See how rapidly the parameters drop, when the product does not touch directly to the steel surface. When planning the arrangement, avoid redundant distances.

Table 2: Vertical capacity (vertical surface)
MW 20x18 / N38

Distance (mm) Friction coefficient Pull Force (kg/lbs/g/N)
0 mm Stal (~0.2) 2.64 kg / 5.82 LBS
2638.0 g / 25.9 N
1 mm Stal (~0.2) 2.13 kg / 4.70 LBS
2134.0 g / 20.9 N
2 mm Stal (~0.2) 1.69 kg / 3.72 LBS
1686.0 g / 16.5 N
3 mm Stal (~0.2) 1.31 kg / 2.89 LBS
1310.0 g / 12.9 N
5 mm Stal (~0.2) 0.76 kg / 1.68 LBS
764.0 g / 7.5 N
10 mm Stal (~0.2) 0.19 kg / 0.42 LBS
190.0 g / 1.9 N
15 mm Stal (~0.2) 0.05 kg / 0.12 LBS
54.0 g / 0.5 N
20 mm Stal (~0.2) 0.02 kg / 0.04 LBS
18.0 g / 0.2 N
30 mm Stal (~0.2) 0.00 kg / 0.01 LBS
4.0 g / 0.0 N
50 mm Stal (~0.2) 0.00 kg / 0.00 LBS
0.0 g / 0.0 N
This section calculates the approximate holding capacity sufficient to initiate the sliding of the magnet downwards against a upright steel plate (considering standard friction coefficient). This parameter depends on the air gap between the magnet and the surface.

Table 3: Vertical assembly (shearing) - behavior on slippery surfaces
MW 20x18 / N38

Surface type Friction coefficient / % Mocy Max load (kg/lbs/g/N)
Raw steel
µ = 0.3 30% Nominalnej Siły
3.96 kg / 8.72 LBS
3957.0 g / 38.8 N
Painted steel (standard)
µ = 0.2 20% Nominalnej Siły
2.64 kg / 5.82 LBS
2638.0 g / 25.9 N
Oily/slippery steel
µ = 0.1 10% Nominalnej Siły
1.32 kg / 2.91 LBS
1319.0 g / 12.9 N
Magnet with anti-slip rubber
µ = 0.5 50% Nominalnej Siły
6.60 kg / 14.54 LBS
6595.0 g / 64.7 N
When mounting a element on a upright wall (e.g., a board), it will only hold only about 1/5 of nominal attraction strength. Gravitational force as well as a low friction coefficient influence the fact that holders slide down faster than they detach. Designing a vertical fastening? Remember that the sliding force is significantly lower than the maximum static pull force. On a smooth steel, the holder will give way down under a noticeably lighter weight. Application of an anti-slip pad can effectively raise the stability.

Table 4: Steel thickness (substrate influence) - sheet metal selection
MW 20x18 / N38

Steel thickness (mm) % power Real pull force (kg/lbs/g/N)
0.5 mm
5%
 0.66 kg / 1.45 LBS
659.5 g / 6.5 N
1 mm
13%
 1.65 kg / 3.63 LBS
1648.8 g / 16.2 N
2 mm
25%
 3.30 kg / 7.27 LBS
3297.5 g / 32.3 N
3 mm
38%
 4.95 kg / 10.90 LBS
4946.3 g / 48.5 N
5 mm
63%
 8.24 kg / 18.17 LBS
8243.8 g / 80.9 N
10 mm
100%
 13.19 kg / 29.08 LBS
13190.0 g / 129.4 N
11 mm
100%
 13.19 kg / 29.08 LBS
13190.0 g / 129.4 N
12 mm
100%
 13.19 kg / 29.08 LBS
13190.0 g / 129.4 N
A too thin steel is incapable of take in the entire magnetic field, which squanders power of the magnet. If you install a neodymium to a thin surface, the magnetism will penetrate right through and the holding will be smaller. To squeeze full efficiency of this magnet's power, you need a suitably thick backing of metal. The material oversaturation means that on delicate walls (e.g., car bodies), the holder holds weaker. We advise picking the steel thickness based on the following data.

Table 5: Thermal stability (stability) - power drop
MW 20x18 / N38

Ambient temp. (°C) Power loss Remaining pull (kg/lbs/g/N) Status
20 °C 0.0% 13.19 kg / 29.08 LBS
13190.0 g / 129.4 N
 OK
40 °C -2.2% 12.90 kg / 28.44 LBS
12899.8 g / 126.5 N
 OK
60 °C -4.4% 12.61 kg / 27.80 LBS
12609.6 g / 123.7 N
 OK
80 °C -6.6% 12.32 kg / 27.16 LBS
12319.5 g / 120.9 N
100 °C -28.8% 9.39 kg / 20.70 LBS
9391.3 g / 92.1 N
Classic neodymiums change their properties strength after exceeding the maximum temperature. Avoid high temperatures – heat can permanently destroy this product. With increasing heat, the magnet's power momentarily drops. Do not use this product close to ovens higher than its working range. Ignoring the limit will lead to irreversible degradation of magnetism.
*Important note: Temperature resistance is determined by both grade, and the Permeance Coefficient Pc. Thin magnets (low permeance coefficient) may lose charge permanently at lower temperatures than long magnets. Warning indicator in the table signals a risk of irreversible loss for this specific geometry.

Table 6: Two magnets (repulsion) - field range
MW 20x18 / N38

Gap (mm) Attraction (kg/lbs) (N-S) Lateral Force (kg/lbs/g/N) Repulsion (kg/lbs) (N-N)
0 mm 56.78 kg / 125.17 LBS
5 968 Gs
8.52 kg / 18.78 LBS
8516 g / 83.5 N
 N/A
1 mm 51.26 kg / 113.01 LBS
10 289 Gs
7.69 kg / 16.95 LBS
7689 g / 75.4 N
 46.13 kg / 101.71 LBS
~0 Gs
2 mm 45.93 kg / 101.25 LBS
9 739 Gs
6.89 kg / 15.19 LBS
6889 g / 67.6 N
 41.33 kg / 91.13 LBS
~0 Gs
3 mm 40.93 kg / 90.24 LBS
9 194 Gs
6.14 kg / 13.54 LBS
6140 g / 60.2 N
 36.84 kg / 81.22 LBS
~0 Gs
5 mm 32.06 kg / 70.68 LBS
8 137 Gs
4.81 kg / 10.60 LBS
4809 g / 47.2 N
 28.86 kg / 63.62 LBS
~0 Gs
10 mm 16.44 kg / 36.24 LBS
5 826 Gs
2.47 kg / 5.44 LBS
2465 g / 24.2 N
 14.79 kg / 32.61 LBS
~0 Gs
20 mm 4.10 kg / 9.04 LBS
2 909 Gs
0.61 kg / 1.36 LBS
615 g / 6.0 N
 3.69 kg / 8.13 LBS
~0 Gs
50 mm 0.15 kg / 0.34 LBS
565 Gs
0.02 kg / 0.05 LBS
23 g / 0.2 N
 0.14 kg / 0.31 LBS
~0 Gs
60 mm 0.07 kg / 0.15 LBS
376 Gs
0.01 kg / 0.02 LBS
10 g / 0.1 N
 0.06 kg / 0.14 LBS
~0 Gs
70 mm 0.03 kg / 0.07 LBS
262 Gs
0.00 kg / 0.01 LBS
5 g / 0.0 N
 0.03 kg / 0.07 LBS
~0 Gs
80 mm 0.02 kg / 0.04 LBS
190 Gs
0.00 kg / 0.01 LBS
3 g / 0.0 N
 0.02 kg / 0.03 LBS
~0 Gs
90 mm 0.01 kg / 0.02 LBS
142 Gs
0.00 kg / 0.00 LBS
1 g / 0.0 N
 0.00 kg / 0.00 LBS
~0 Gs
100 mm 0.01 kg / 0.01 LBS
109 Gs
0.00 kg / 0.00 LBS
1 g / 0.0 N
 0.00 kg / 0.00 LBS
~0 Gs
Two magnets attract each other from a significantly greater distance than a neodymium and metal setup. Such a system of two magnets produces a massive flux and a further horizon of operation. Want to build a strong closure? Utilize two neodymiums instead of one magnet and a striker plate. Exercise caution that when connecting a pair of magnets, the collision energy is huge. The repulsion force is slightly lower than the attraction, but still impressive.
*Flux density for N-N configuration reaches ~0 Gs in the exact middle between the magnets (resulting from vector opposition).
Note: Results refer to shear force of a pair of identical magnets (friction ~0.15 for Ni-Ni layer).

Table 7: Hazards (implants) - warnings
MW 20x18 / N38

Object / Device Limit (Gauss) / mT Safe distance
Pacemaker 5 Gs (0.5 mT) 12.5 cm
Hearing aid 10 Gs (1.0 mT) 9.5 cm
Mechanical watch 20 Gs (2.0 mT) 7.5 cm
Mobile device 40 Gs (4.0 mT) 6.0 cm
Remote 50 Gs (5.0 mT) 5.5 cm
Payment card 400 Gs (40.0 mT) 2.5 cm
HDD hard drive 600 Gs (60.0 mT) 2.0 cm
Extremely neodym field poses a real danger to electronics as well as pacemakers. These magnets produce a field that destroys function of digital equipment. Be aware: the invisible magnetic field acts through matter and plastic. Increased vigilance must be taken by people with cochlear implants and insulin pumps. Also at risk are: automatic timepieces, remotes, membranes, and displays. Do not bring the product near payment cards, HDD media, or precise measuring instruments.

Table 8: Dynamics (kinetic energy) - collision effects
MW 20x18 / N38

Start from (mm) Speed (km/h) Energy (J) Predicted outcome
10 mm 17.20 km/h
(4.78 m/s)
 0.48 J
30 mm 17.87 km/h
(4.96 m/s)
 0.52 J
50 mm 17.89 km/h
(4.97 m/s)
 0.52 J
100 mm 17.89 km/h
(4.97 m/s)
 0.52 J
Neodymium magnets are very brittle – a collision with steel can result in shattering. Pay attention to connection velocity – a neodymium left loose becomes dangerous. Kinetic force can trigger coating fragments or painful pinches to fingers. Be sure to control the product during installation so it doesn't slam with momentum against the steel surface. A collision at high speed means shattering of the neodymium. Wear eye protection when handling with powerful specimens.

Table 9: Anti-corrosion coating durability
MW 20x18 / 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)
For outdoor applications, an epoxy coating is required; standard nickel is intended for indoor use. The silver nickel coating also serves an aesthetic function but is not fully waterproof.

Table 10: Construction data (Flux)
MW 20x18 / N38

Parameter Value SI Unit / Description
Magnetic Flux 17 374 Mx 173.7 µWb
Pc Coefficient 0.85 High (Stable)
Total magnetic flux passing through the magnet pole. Essential parameter for generator designers and motors. The Pc coefficient determines the magnet's operating point.

Table 11: Physics of underwater searching
MW 20x18 / N38

Environment Effective steel pull Effect
Air (land) 13.19 kg Standard
Water (riverbed) 15.10 kg
(+1.91 kg buoyancy gain)
+14.5%
Warning: Remember to wipe the magnet thoroughly after removing it from water and apply a protective layer (e.g., oil) to avoid corrosion.
In water, the magnet feels stronger thanks to Archimedes' principle. Note: for permanent underwater work, we recommend magnets with an anti-corrosive (epoxy) coating.

1. Vertical hold

*Warning: On a vertical wall, the magnet holds merely approx. 20-30% of its nominal pull.

2. Steel saturation

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

3. Heat tolerance

*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) = 0.85

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

Elemental analysis

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%

Ecology and recycling (GPSR)

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: 010040-2026
Magnet Unit Converter

Force (pull)

Field Strength

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This product is an extremely powerful cylinder magnet, composed of modern NdFeB material, which, at dimensions of Ø20x18 mm, guarantees the highest energy density. The MW 20x18 / N38 component features high dimensional repeatability and professional build quality, making it a perfect solution for the most demanding engineers and designers. As a cylindrical magnet with significant force (approx. 13.19 kg), this product is available off-the-shelf from our European logistics center, ensuring rapid order fulfillment. Additionally, its Ni-Cu-Ni coating secures it against corrosion in typical operating conditions, ensuring an aesthetic appearance and durability for years.
This model is perfect for building generators, advanced sensors, and efficient magnetic separators, where maximum induction on a small surface counts. Thanks to the high power of 129.35 N with a weight of only 42.41 g, this cylindrical magnet is indispensable in electronics and wherever low weight is crucial.
Due to the delicate structure of the ceramic sinter, you must not use force-fitting (so-called press-fit), as this risks immediate cracking of this precision component. To ensure stability in industry, anaerobic resins are used, which do not react with the nickel coating and fill the gap, guaranteeing high repeatability of the connection.
Magnets NdFeB grade N38 are suitable for 90% of applications in modeling and machine building, where extreme miniaturization with maximum force is not required. If you need even stronger magnets in the same volume (Ø20x18), contact us regarding higher grades (e.g., N50, N52), however, N38 is the standard in continuous sale in our warehouse.
The presented product is a neodymium magnet with precisely defined parameters: diameter 20 mm and height 18 mm. The value of 129.35 N means that the magnet is capable of holding a weight many times exceeding its own mass of 42.41 g. The product has a [NiCuNi] coating, which secures it against oxidation, giving it an aesthetic, silvery shine.
Standardly, the magnetic axis runs through the center of the cylinder, causing the greatest attraction force to occur on the bases with a diameter of 20 mm. Such an arrangement is most desirable when connecting magnets in stacks (e.g., in filters) or when mounting in sockets at the bottom of a hole. On request, we can also produce versions magnetized diametrically if your project requires it.

Strengths as well as weaknesses of neodymium magnets.

Pros

Besides their stability, neodymium magnets are valued for these benefits:
  • Their magnetic field is maintained, and after around ten years it drops only by ~1% (theoretically),
  • They retain their magnetic properties even under external field action,
  • The use of an shiny coating of noble metals (nickel, gold, silver) causes the element to present itself better,
  • The surface of neodymium magnets generates a concentrated magnetic field – this is one of their assets,
  • Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can work (depending on the shape) even at a temperature of 230°C or more...
  • Considering the ability of flexible shaping and customization to unique needs, magnetic components can be manufactured in a broad palette of shapes and sizes, which makes them more universal,
  • Key role in advanced technology sectors – they are commonly used in computer drives, drive modules, diagnostic systems, as well as industrial machines.
  • Compactness – despite small sizes they generate large force, making them ideal for precision applications

Limitations

Disadvantages of neodymium magnets:
  • Susceptibility to cracking is one of their disadvantages. Upon intense impact they can break. We recommend keeping them in a special holder, which not only secures them against impacts but also raises their durability
  • Neodymium magnets lose their force under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
  • Due to the susceptibility of magnets to corrosion in a humid environment, we advise using waterproof magnets made of rubber, plastic or other material resistant to moisture, when using outdoors
  • Due to limitations in realizing nuts and complex forms in magnets, we recommend using casing - magnetic mechanism.
  • Health risk resulting from small fragments of magnets can be dangerous, in case of ingestion, which becomes key in the context of child safety. Furthermore, tiny parts of these products are able to disrupt the diagnostic process medical in case of swallowing.
  • Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Pull force analysis

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

The force parameter is a theoretical maximum value performed under the following configuration:
  • with the use of a sheet made of low-carbon steel, guaranteeing full magnetic saturation
  • possessing a massiveness of at least 10 mm to ensure full flux closure
  • with an ideally smooth touching surface
  • without the slightest air gap between the magnet and steel
  • during detachment in a direction perpendicular to the mounting surface
  • at room temperature

What influences lifting capacity in practice

It is worth knowing that the magnet holding may be lower subject to elements below, in order of importance:
  • Distance (between the magnet and the metal), because even a very small distance (e.g. 0.5 mm) results in a decrease in force by up to 50% (this also applies to varnish, corrosion or debris).
  • Force direction – catalog parameter refers to pulling vertically. When applying parallel force, the magnet exhibits significantly lower power (often approx. 20-30% of nominal force).
  • Substrate thickness – to utilize 100% power, the steel must be sufficiently thick. Thin sheet restricts the attraction force (the magnet "punches through" it).
  • Material type – the best choice is high-permeability steel. Stainless steels may attract less.
  • Surface condition – ground elements ensure maximum contact, which improves force. Rough surfaces reduce efficiency.
  • Temperature influence – high temperature weakens magnetic field. Exceeding the limit temperature can permanently demagnetize the magnet.

Holding force was tested on the plate surface of 20 mm thickness, when the force acted perpendicularly, whereas under attempts to slide the magnet the holding force is lower. Moreover, even a small distance between the magnet and the plate lowers the holding force.

Safety rules for work with neodymium magnets
Compass and GPS

An intense magnetic field disrupts the operation of compasses in phones and navigation systems. Do not bring magnets close to a smartphone to avoid damaging the sensors.

Cards and drives

Avoid bringing magnets close to a purse, computer, or screen. The magnetism can permanently damage these devices and erase data from cards.

Warning for heart patients

For implant holders: Powerful magnets disrupt medical devices. Keep minimum 30 cm distance or request help to handle the magnets.

Physical harm

Big blocks can crush fingers instantly. Do not put your hand betwixt two attracting surfaces.

Power loss in heat

Regular neodymium magnets (N-type) undergo demagnetization when the temperature exceeds 80°C. Damage is permanent.

Product not for children

Neodymium magnets are not intended for children. Swallowing multiple magnets may result in them attracting across intestines, which constitutes a critical condition and requires urgent medical intervention.

Allergic reactions

Certain individuals experience a sensitization to nickel, which is the typical protective layer for NdFeB magnets. Extended handling can result in a rash. It is best to wear protective gloves.

Caution required

Handle magnets consciously. Their huge power can shock even professionals. Be vigilant and respect their force.

Do not drill into magnets

Dust created during cutting of magnets is self-igniting. Avoid drilling into magnets without proper cooling and knowledge.

Material brittleness

NdFeB magnets are sintered ceramics, meaning they are fragile like glass. Impact of two magnets leads to them breaking into small pieces.

Safety First! More info about hazards in the article: Safety of working with magnets.