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MW 15x4 / N38 - cylindrical magnet

cylindrical magnet

Catalog no 010030

GTIN/EAN: 5906301810292

5.00
Load capacity 4.22 kg / 41.38 N Magnetic Induction 291.60 mT / 2916 Gs
Diameter Ø
15 mm [±0,1 mm]
Height
4 mm [±0,1 mm]
Weight
5.3 g
Magnetization Direction
↑ axial
Coating
[NiCuNi] Nickel

How we measure these parameters — certificates and measurements

product specifications »

1.600 zł net / pcs

1.968 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 data - MW 15x4 / N38 - cylindrical magnet

Specification / characteristics - MW 15x4 / N38 - cylindrical magnet

properties
properties values
Cat. no. 010030
GTIN/EAN 5906301810292
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 15 mm [±0,1 mm]
Height 4 mm [±0,1 mm]
Weight 5.3 g
Magnetization Direction ↑ axial
Load capacity ~ ? 4.22 kg / 41.38 N
Magnetic Induction ~ ? 291.60 mT / 2916 Gs
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±0.1 mm

Magnetic properties of material N38

Specification / characteristics MW 15x4 / 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 simulation of the assembly - technical parameters

These information represent the direct effect of a mathematical analysis. Values rely on algorithms for the class Nd2Fe14B. Operational parameters might slightly differ from theoretical values. Use these calculations as a reference point when designing systems.

Table 1: Static force (force vs gap) - power drop
MW 15x4 / N38

Distance (mm) Induction (Gauss) / mT Pull Force (kg/lbs/g/N) Risk Status
0 mm 2915 Gs
291.5 mT
 4.22 kg / 9.30 LBS
4220.0 g / 41.4 N
 medium risk
1 mm 2620 Gs
262.0 mT
 3.41 kg / 7.51 LBS
3408.2 g / 33.4 N
 medium risk
2 mm 2276 Gs
227.6 mT
 2.57 kg / 5.67 LBS
2571.6 g / 25.2 N
 medium risk
3 mm 1928 Gs
192.8 mT
 1.85 kg / 4.07 LBS
1845.5 g / 18.1 N
 safe
5 mm 1324 Gs
132.4 mT
 0.87 kg / 1.92 LBS
870.3 g / 8.5 N
 safe
10 mm 505 Gs
50.5 mT
 0.13 kg / 0.28 LBS
126.7 g / 1.2 N
 safe
15 mm 222 Gs
22.2 mT
 0.02 kg / 0.05 LBS
24.4 g / 0.2 N
 safe
20 mm 113 Gs
11.3 mT
 0.01 kg / 0.01 LBS
6.3 g / 0.1 N
 safe
30 mm 40 Gs
4.0 mT
 0.00 kg / 0.00 LBS
0.8 g / 0.0 N
 safe
50 mm 10 Gs
1.0 mT
 0.00 kg / 0.00 LBS
0.0 g / 0.0 N
 safe
Pulling power decreases drastically per each millimeter of gap. Keep in mind that every additional insulation layer (e.g., dirt, varnish, dust) strongly reduces the pull force. Magnets operate strongest at the point of direct contact; distance weakens the force. Analyze how quickly the load capacity fall, when the magnet does not adhere flatly to the steel surface. When designing the mounting, eliminate unnecessary gaps.

Table 2: Vertical hold (wall)
MW 15x4 / N38

Distance (mm) Friction coefficient Pull Force (kg/lbs/g/N)
0 mm Stal (~0.2) 0.84 kg / 1.86 LBS
844.0 g / 8.3 N
1 mm Stal (~0.2) 0.68 kg / 1.50 LBS
682.0 g / 6.7 N
2 mm Stal (~0.2) 0.51 kg / 1.13 LBS
514.0 g / 5.0 N
3 mm Stal (~0.2) 0.37 kg / 0.82 LBS
370.0 g / 3.6 N
5 mm Stal (~0.2) 0.17 kg / 0.38 LBS
174.0 g / 1.7 N
10 mm Stal (~0.2) 0.03 kg / 0.06 LBS
26.0 g / 0.3 N
15 mm Stal (~0.2) 0.00 kg / 0.01 LBS
4.0 g / 0.0 N
20 mm Stal (~0.2) 0.00 kg / 0.00 LBS
2.0 g / 0.0 N
30 mm Stal (~0.2) 0.00 kg / 0.00 LBS
0.0 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 theoretical weight limit needed to initiate the slippage of the magnet vertically on a upright metal surface (assuming standard friction). This value varies with the gap size between the magnet and the metal.

Table 3: Vertical assembly (sliding) - vertical pull
MW 15x4 / N38

Surface type Friction coefficient / % Mocy Max load (kg/lbs/g/N)
Raw steel
µ = 0.3 30% Nominalnej Siły
1.27 kg / 2.79 LBS
1266.0 g / 12.4 N
Painted steel (standard)
µ = 0.2 20% Nominalnej Siły
0.84 kg / 1.86 LBS
844.0 g / 8.3 N
Oily/slippery steel
µ = 0.1 10% Nominalnej Siły
0.42 kg / 0.93 LBS
422.0 g / 4.1 N
Magnet with anti-slip rubber
µ = 0.5 50% Nominalnej Siły
2.11 kg / 4.65 LBS
2110.0 g / 20.7 N
When mounting a magnet on a upright plane (e.g., a car body), it will only hold only approx. 1/5 of nominal attraction strength. Gravity and a low friction coefficient mean that magnets slide down easier than they detach. Want to create a wall mount? Note that the sliding force is significantly lower than the perpendicular breakaway force. On a slippery surface, the magnet will give way down under a much lighter load. Application of an anti-slip layer can effectively improve the result.

Table 4: Steel thickness (substrate influence) - sheet metal selection
MW 15x4 / N38

Steel thickness (mm) % power Real pull force (kg/lbs/g/N)
0.5 mm
10%
 0.42 kg / 0.93 LBS
422.0 g / 4.1 N
1 mm
25%
 1.06 kg / 2.33 LBS
1055.0 g / 10.3 N
2 mm
50%
 2.11 kg / 4.65 LBS
2110.0 g / 20.7 N
3 mm
75%
 3.17 kg / 6.98 LBS
3165.0 g / 31.0 N
5 mm
100%
 4.22 kg / 9.30 LBS
4220.0 g / 41.4 N
10 mm
100%
 4.22 kg / 9.30 LBS
4220.0 g / 41.4 N
11 mm
100%
 4.22 kg / 9.30 LBS
4220.0 g / 41.4 N
12 mm
100%
 4.22 kg / 9.30 LBS
4220.0 g / 41.4 N
A too thin steel is unable to take in the entire magnetic field, which wastes potential of the holder. Should you install a neodymium to a weak sheet, the magnetism will penetrate right through and the pull force will drop sharply. To utilize the maximum of this neodymium's power, you need a suitably thick backing of steel. The saturation effect means that on delicate walls (e.g., appliance housings), the holder shows lower pull force. We recommend selecting the steel dimension based on the following data.

Table 5: Thermal resistance (stability) - resistance threshold
MW 15x4 / N38

Ambient temp. (°C) Power loss Remaining pull (kg/lbs/g/N) Status
20 °C 0.0% 4.22 kg / 9.30 LBS
4220.0 g / 41.4 N
 OK
40 °C -2.2% 4.13 kg / 9.10 LBS
4127.2 g / 40.5 N
 OK
60 °C -4.4% 4.03 kg / 8.89 LBS
4034.3 g / 39.6 N
80 °C -6.6% 3.94 kg / 8.69 LBS
3941.5 g / 38.7 N
100 °C -28.8% 3.00 kg / 6.62 LBS
3004.6 g / 29.5 N
Standard neodymium magnets irreversibly lose power above the temperature limit. Protect against heat – excessive heat can permanently destroy this magnet. With every degree above norm, the magnet's capacity momentarily drops. Avoid using this magnet close to heaters higher than its working range. Ignoring the limit will cause irreversible degradation of magnetism.
*Important note: Heat tolerance depends not only on the material grade, but also on the magnet's shape. Low-profile magnets (low permeance coefficient) may lose charge permanently at lower temperatures than taller cylinders. Warning indicator in the table signals permanent field degradation for this particular item.

Table 6: Two magnets (attraction) - field range
MW 15x4 / N38

Gap (mm) Attraction (kg/lbs) (N-S) Shear Strength (kg/lbs/g/N) Repulsion (kg/lbs) (N-N)
0 mm 9.26 kg / 20.41 LBS
4 518 Gs
1.39 kg / 3.06 LBS
1389 g / 13.6 N
 N/A
1 mm 8.40 kg / 18.53 LBS
5 555 Gs
1.26 kg / 2.78 LBS
1261 g / 12.4 N
 7.56 kg / 16.68 LBS
~0 Gs
2 mm 7.48 kg / 16.48 LBS
5 239 Gs
1.12 kg / 2.47 LBS
1122 g / 11.0 N
 6.73 kg / 14.84 LBS
~0 Gs
3 mm 6.54 kg / 14.42 LBS
4 901 Gs
0.98 kg / 2.16 LBS
981 g / 9.6 N
 5.89 kg / 12.98 LBS
~0 Gs
5 mm 4.80 kg / 10.59 LBS
4 200 Gs
0.72 kg / 1.59 LBS
721 g / 7.1 N
 4.32 kg / 9.53 LBS
~0 Gs
10 mm 1.91 kg / 4.21 LBS
2 648 Gs
0.29 kg / 0.63 LBS
286 g / 2.8 N
 1.72 kg / 3.79 LBS
~0 Gs
20 mm 0.28 kg / 0.61 LBS
1 010 Gs
0.04 kg / 0.09 LBS
42 g / 0.4 N
 0.25 kg / 0.55 LBS
~0 Gs
50 mm 0.00 kg / 0.01 LBS
128 Gs
0.00 kg / 0.00 LBS
1 g / 0.0 N
 0.00 kg / 0.00 LBS
~0 Gs
60 mm 0.00 kg / 0.00 LBS
79 Gs
0.00 kg / 0.00 LBS
0 g / 0.0 N
 0.00 kg / 0.00 LBS
~0 Gs
70 mm 0.00 kg / 0.00 LBS
52 Gs
0.00 kg / 0.00 LBS
0 g / 0.0 N
 0.00 kg / 0.00 LBS
~0 Gs
80 mm 0.00 kg / 0.00 LBS
36 Gs
0.00 kg / 0.00 LBS
0 g / 0.0 N
 0.00 kg / 0.00 LBS
~0 Gs
90 mm 0.00 kg / 0.00 LBS
26 Gs
0.00 kg / 0.00 LBS
0 g / 0.0 N
 0.00 kg / 0.00 LBS
~0 Gs
100 mm 0.00 kg / 0.00 LBS
19 Gs
0.00 kg / 0.00 LBS
0 g / 0.0 N
 0.00 kg / 0.00 LBS
~0 Gs
Two magnetic products attract each other from a wider radius than a neodymium and metal setup. The setup of magnet-to-magnet generates a stronger field and a wider radius of performance. Designing a solid fastener? Use a pair of magnets instead of one magnet and a steel. Be careful that when connecting a pair of magnets, the impact force is extreme. The levitation is a bit weaker than the attraction, but still significant.
*The magnetic induction in repulsion mode reaches ~0 Gs at the geometric center between the magnets (caused by magnetic field nullification).
Attention: Figures demonstrate shear force of a pair of identical magnets (friction coefficient ~0.15 for Ni-Ni plating).

Table 7: Safety (HSE) (electronics) - warnings
MW 15x4 / N38

Object / Device Limit (Gauss) / mT Safe distance
Pacemaker 5 Gs (0.5 mT) 6.5 cm
Hearing aid 10 Gs (1.0 mT) 5.0 cm
Mechanical watch 20 Gs (2.0 mT) 4.0 cm
Mobile device 40 Gs (4.0 mT) 3.0 cm
Remote 50 Gs (5.0 mT) 3.0 cm
Payment card 400 Gs (40.0 mT) 1.5 cm
HDD hard drive 600 Gs (60.0 mT) 1.0 cm
A strong magnetic field poses a large risk to IT equipment and pacemakers. These NdFeB products generate a field that prevents correct functioning of digital equipment. Notice: the unseen radiation passes through tissues and glass. Special caution must be taken by people with cochlear implants and insulin pumps. Influence will be felt by: automatic timepieces, car keys, speakers, and screens. Do not bring the product near payment cards, hard drives, or precise measuring instruments.

Table 8: Dynamics (cracking risk) - warning
MW 15x4 / N38

Start from (mm) Speed (km/h) Energy (J) Predicted outcome
10 mm 25.48 km/h
(7.08 m/s)
 0.13 J
30 mm 25.84 km/h
(7.18 m/s)
 0.14 J
50 mm 25.85 km/h
(7.18 m/s)
 0.14 J
100 mm 25.85 km/h
(7.18 m/s)
 0.14 J
NdFeB products are delicate – a collision with steel risks their cracking. Watch the impact speed – a neodymium left loose speeds with massive force. Kinetic force can cause material chips or dangerous crushing to skin. Always hold the magnet during bringing near metal so it doesn't hit violently against the metal. A collision at high speed almost guarantees destruction of the magnet. Wear safety glasses when playing with powerful specimens.

Table 9: Corrosion resistance
MW 15x4 / 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 SST (salt spray test) is an industry standard for determining coating lifespan in harsh conditions. The silver nickel coating also serves an aesthetic function but is not fully waterproof.

Table 10: Electrical data (Pc)
MW 15x4 / N38

Parameter Value SI Unit / Description
Magnetic Flux 5 659 Mx 56.6 µWb
Pc Coefficient 0.37 Low (Flat)
Total magnetic flux emitted by the magnet pole. Essential parameter in coil applications as well as sensors. The Pc coefficient determines the magnet's operating point.

Table 11: Hydrostatics and buoyancy
MW 15x4 / N38

Environment Effective steel pull Effect
Air (land) 4.22 kg Standard
Water (riverbed) 4.83 kg
(+0.61 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.
Water displaces steel, making heavy objects slightly lighter. As a result, your magnet will pull a heavier object from the bottom than if you lifted it in the air.

1. Shear force

*Caution: On a vertical surface, the magnet holds just approx. 20-30% of its perpendicular strength.

2. Plate thickness effect

*Thin steel (e.g. 0.5mm PC case) significantly weakens the holding force.

3. Heat tolerance

*For standard magnets, the max working temp is 80°C.

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

chart generated for the permeance coefficient Pc (Permeance Coefficient) = 0.37

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 specification and ecology

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%

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: 010030-2026
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This product is a very strong cylindrical magnet, manufactured from modern NdFeB material, which, with dimensions of Ø15x4 mm, guarantees optimal power. This specific item is characterized by a tolerance of ±0.1mm and professional build quality, making it a perfect solution for the most demanding engineers and designers. As a cylindrical magnet with impressive force (approx. 4.22 kg), this product is in stock from our European logistics center, ensuring quick order fulfillment. Moreover, its triple-layer Ni-Cu-Ni coating effectively protects it against corrosion in typical operating conditions, ensuring an aesthetic appearance and durability for years.
This model is perfect for building generators, advanced Hall effect sensors, and efficient filters, where field concentration on a small surface counts. Thanks to the high power of 41.38 N with a weight of only 5.3 g, this rod is indispensable in miniature devices 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 chipping the coating of this professional component. To ensure stability in industry, specialized industrial adhesives are used, which do not react with the nickel coating and fill the gap, guaranteeing durability of the connection.
Magnets NdFeB grade N38 are strong enough for 90% of applications in modeling and machine building, where excessive miniaturization with maximum force is not required. If you need the strongest magnets in the same volume (Ø15x4), contact us regarding higher grades (e.g., N50, N52), however, N38 is the standard available off-the-shelf in our store.
The presented product is a neodymium magnet with precisely defined parameters: diameter 15 mm and height 4 mm. The key parameter here is the lifting capacity amounting to approximately 4.22 kg (force ~41.38 N), which, with such compact dimensions, proves the high grade of the NdFeB material. 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 15 mm. Thanks to this, the magnet can be easily glued into a hole and achieve a strong field on the front surface. On request, we can also produce versions magnetized through the diameter if your project requires it.

Strengths and weaknesses of rare earth magnets.

Pros

Apart from their superior holding force, neodymium magnets have these key benefits:
  • They do not lose strength, even after approximately 10 years – the reduction in lifting capacity is only ~1% (based on measurements),
  • Magnets very well protect themselves against demagnetization caused by ambient magnetic noise,
  • Thanks to the metallic finish, the layer of Ni-Cu-Ni, gold-plated, or silver gives an modern appearance,
  • Neodymium magnets create maximum magnetic induction on a their surface, which increases force concentration,
  • Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can function (depending on the shape) even at a temperature of 230°C or more...
  • Thanks to flexibility in shaping and the ability to adapt to individual projects,
  • Key role in advanced technology sectors – they serve a role in hard drives, motor assemblies, advanced medical instruments, also multitasking production systems.
  • Compactness – despite small sizes they generate large force, making them ideal for precision applications

Weaknesses

Disadvantages of NdFeB magnets:
  • To avoid cracks under impact, we recommend using special steel housings. Such a solution secures the magnet and simultaneously improves its durability.
  • When exposed to high temperature, neodymium magnets experience a drop in power. Often, when the temperature exceeds 80°C, their power decreases (depending on the size, as well as shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
  • Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material resistant to moisture, in case of application outdoors
  • Due to limitations in realizing nuts and complex forms in magnets, we propose using cover - magnetic holder.
  • Health risk related to microscopic parts of magnets can be dangerous, in case of ingestion, which gains importance in the context of child health protection. It is also worth noting that small elements of these magnets are able to disrupt the diagnostic process medical in case of swallowing.
  • Due to expensive raw materials, their price is higher than average,

Pull force analysis

Best holding force of the magnet in ideal parameters – what contributes to it?

Holding force of 4.22 kg is a measurement result conducted under specific, ideal conditions:
  • using a sheet made of low-carbon steel, serving as a magnetic yoke
  • possessing a thickness of at least 10 mm to avoid saturation
  • with an polished contact surface
  • with direct contact (no paint)
  • under perpendicular force direction (90-degree angle)
  • in stable room temperature

Practical aspects of lifting capacity – factors

It is worth knowing that the working load may be lower influenced by elements below, in order of importance:
  • Space between surfaces – even a fraction of a millimeter of distance (caused e.g. by varnish or dirt) significantly weakens the pulling force, often by half at just 0.5 mm.
  • Direction of force – maximum parameter is obtained only during pulling at a 90° angle. The force required to slide of the magnet along the surface is standardly many times lower (approx. 1/5 of the lifting capacity).
  • Wall thickness – thin material does not allow full use of the magnet. Magnetic flux passes through the material instead of generating force.
  • Chemical composition of the base – mild steel attracts best. Alloy admixtures decrease magnetic permeability and holding force.
  • Smoothness – ideal contact is possible only on polished steel. Any scratches and bumps reduce the real contact area, reducing force.
  • Thermal environment – temperature increase results in weakening of induction. It is worth remembering the thermal limit for a given model.

Holding force was measured on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, whereas under attempts to slide the magnet the load capacity is reduced by as much as fivefold. In addition, even a small distance between the magnet and the plate lowers the holding force.

Safety rules for work with NdFeB magnets
Do not give to children

Adult use only. Tiny parts pose a choking risk, leading to severe trauma. Keep away from children and animals.

Do not drill into magnets

Mechanical processing of NdFeB material carries a risk of fire hazard. Neodymium dust reacts violently with oxygen and is difficult to extinguish.

Electronic hazard

Device Safety: Strong magnets can damage payment cards and sensitive devices (pacemakers, medical aids, mechanical watches).

GPS Danger

Navigation devices and mobile phones are highly sensitive to magnetic fields. Close proximity with a strong magnet can ruin the sensors in your phone.

Material brittleness

Beware of splinters. Magnets can fracture upon uncontrolled impact, ejecting sharp fragments into the air. We recommend safety glasses.

Implant safety

Individuals with a heart stimulator have to maintain an large gap from magnets. The magnetism can stop the functioning of the life-saving device.

Immense force

Handle with care. Rare earth magnets act from a distance and snap with huge force, often quicker than you can move away.

Operating temperature

Watch the temperature. Exposing the magnet to high heat will permanently weaken its properties and pulling force.

Bone fractures

Big blocks can crush fingers instantly. Under no circumstances place your hand between two attracting surfaces.

Nickel coating and allergies

Studies show that the nickel plating (standard magnet coating) is a potent allergen. If you have an allergy, prevent direct skin contact and choose coated magnets.

Security! Need more info? Check our post: Are neodymium magnets dangerous?