Product available Ships in 2 days

MP 20x8/4x5 / N38 - ring magnet

Name: Dhit sp. z o.o.
Address: Kościuszki 6A, Ożarów Mazowiecki, Poland, 05-850, PL
Telephone: +48 22 499 98 98
Price range: PLN 1-6500
Rating: 5

ring magnet

Catalog no 030333

GTIN/EAN: 5906301812272

5.00

Diameter

20 mm [±0,1 mm]

internal diameter Ø

8/4 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

11.31 g

Magnetization Direction

↑ axial

Load capacity

6.65 kg / 65.21 N

Magnetic Induction

277.16 mT / 2772 Gs

Coating

[NiCuNi] Nickel

product parameters »

7.75 ZŁ with VAT / pcs + price for transport

6.30 ZŁ net + 23% VAT / pcs

bulk discounts:

Need more?

price from 1 pcs

6.30 ZŁ

7.75 ZŁ

price from 100 pcs

5.92 ZŁ

7.28 ZŁ

price from 400 pcs

5.54 ZŁ

6.82 ZŁ

Carbon Footprint – environmental impact GPSR Regulation – product safety

Need advice?

Call us +48 888 99 98 98 alternatively get in touch through form through our site.
Specifications as well as shape of magnets can be estimated with our force calculator.

Same-day shipping for orders placed before 14:00.

Product card - MP 20x8/4x5 / N38 - ring magnet

Specification / characteristics - MP 20x8/4x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030333
GTIN/EAN	5906301812272
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	20 mm [±0,1 mm]
internal diameter Ø	8/4 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	11.31 g
Magnetization Direction	↑ axial
Load capacity ~ ?	6.65 kg / 65.21 N
Magnetic Induction ~ ?	277.16 mT / 2772 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 20x8/4x5 / N38 - ring magnet

properties	values	units
remenance Br [min. - max.] ?	12.2-12.6	kGs
remenance Br [min. - max.] ?	1220-1260	mT
coercivity bHc ?	10.8-11.5	kOe
coercivity bHc ?	860-915	kA/m
actual internal force iHc	≥ 12	kOe
actual internal force iHc	≥ 955	kA/m
energy density [min. - max.] ?	36-38	BH max MGOe
energy density [min. - max.] ?	287-303	BH max KJ/m
max. temperature ?	≤ 80	°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	312 - 380	°C
Curie Temperature TF	593 - 716	°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 analysis of the product - technical parameters

The following values represent the direct effect of a physical calculation. Values were calculated on algorithms for the class Nd₂Fe₁₄B. Real-world conditions may differ from theoretical values. Use these data as a reference point when designing systems.

Table 1: Static force (force vs gap) - characteristics
MP 20x8/4x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	2424 Gs 242.4 mT	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N	strong
1 mm	2265 Gs 226.5 mT	5.81 kg / 12.80 LBS 5807.9 g / 57.0 N	strong
2 mm	2070 Gs 207.0 mT	4.85 kg / 10.69 LBS 4851.0 g / 47.6 N	strong
3 mm	1858 Gs 185.8 mT	3.91 kg / 8.61 LBS 3906.5 g / 38.3 N	strong
5 mm	1437 Gs 143.7 mT	2.34 kg / 5.16 LBS 2338.7 g / 22.9 N	strong
10 mm	691 Gs 69.1 mT	0.54 kg / 1.19 LBS 540.5 g / 5.3 N	safe
15 mm	343 Gs 34.3 mT	0.13 kg / 0.29 LBS 133.3 g / 1.3 N	safe
20 mm	186 Gs 18.6 mT	0.04 kg / 0.09 LBS 39.3 g / 0.4 N	safe
30 mm	70 Gs 7.0 mT	0.01 kg / 0.01 LBS 5.5 g / 0.1 N	safe
50 mm	18 Gs 1.8 mT	0.00 kg / 0.00 LBS 0.4 g / 0.0 N	safe

Magnetic force decreases drastically with every subsequent millimeter of distance. Remember that even a very thin break (e.g., dirt, varnish, rust) noticeably diminishes the holding power. Magnetic products operate most effectively in perfect adhesion; air break kills the force. See how quickly the parameters fall, when the product does not adhere tightly to the metal substrate. When planning the mounting, avoid unnecessary gaps.

Table 2: Slippage capacity (vertical surface)
MP 20x8/4x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.33 kg / 2.93 LBS 1330.0 g / 13.0 N
1 mm	Stal (~0.2)	1.16 kg / 2.56 LBS 1162.0 g / 11.4 N
2 mm	Stal (~0.2)	0.97 kg / 2.14 LBS 970.0 g / 9.5 N
3 mm	Stal (~0.2)	0.78 kg / 1.72 LBS 782.0 g / 7.7 N
5 mm	Stal (~0.2)	0.47 kg / 1.03 LBS 468.0 g / 4.6 N
10 mm	Stal (~0.2)	0.11 kg / 0.24 LBS 108.0 g / 1.1 N
15 mm	Stal (~0.2)	0.03 kg / 0.06 LBS 26.0 g / 0.3 N
20 mm	Stal (~0.2)	0.01 kg / 0.02 LBS 8.0 g / 0.1 N
30 mm	Stal (~0.2)	0.00 kg / 0.00 LBS 2.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 LBS 0.0 g / 0.0 N

This section defines the estimated force required to start the slippage of the magnet vertically along a upright metal surface (considering standard friction coefficient). This parameter depends on the distance between the magnet and the metal.

Table 3: Wall mounting (shearing) - vertical pull
MP 20x8/4x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	2.00 kg / 4.40 LBS 1995.0 g / 19.6 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.33 kg / 2.93 LBS 1330.0 g / 13.0 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.67 kg / 1.47 LBS 665.0 g / 6.5 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	3.33 kg / 7.33 LBS 3325.0 g / 32.6 N

When placing a element on a vertical plane (e.g., a board), it will only hold only approx. 1/5 of nominal attraction strength. Gravity as well as a low friction coefficient influence the fact that holders slide down faster than they pop off the substrate. Designing a wall mount? Remember that the sliding force is noticeably lower than the maximum static pull force. On a painted metal, the element will give way down under a noticeably lighter weight. Using a rubber layer can effectively improve the result.

Table 4: Material efficiency (saturation) - sheet metal selection
MP 20x8/4x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.67 kg / 1.47 LBS 665.0 g / 6.5 N
1 mm	25%	1.66 kg / 3.67 LBS 1662.5 g / 16.3 N
2 mm	50%	3.33 kg / 7.33 LBS 3325.0 g / 32.6 N
3 mm	75%	4.99 kg / 11.00 LBS 4987.5 g / 48.9 N
5 mm	100%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N
10 mm	100%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N
11 mm	100%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N
12 mm	100%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N

A thin metal plate is incapable of focus the full magnetic flux, which weakens actual performance of the magnet. Should you attach a powerful product to a thin surface, the field will pass right through and the holding will be smaller. To squeeze the maximum of this neodymium's potential, you require a sufficiently solid backing of metal. The material oversaturation causes that on delicate walls (e.g., thin profiles), the holder holds weaker. We advise picking the steel dimension from these parameters.

Table 5: Thermal stability (material behavior) - resistance threshold
MP 20x8/4x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N	OK
40 °C	-2.2%	6.50 kg / 14.34 LBS 6503.7 g / 63.8 N	OK
60 °C	-4.4%	6.36 kg / 14.02 LBS 6357.4 g / 62.4 N
80 °C	-6.6%	6.21 kg / 13.69 LBS 6211.1 g / 60.9 N
100 °C	-28.8%	4.73 kg / 10.44 LBS 4734.8 g / 46.4 N

Classic neodymiums lose parameters past the thermal threshold. Protect against heat – high temperature can irreversibly destroy this magnet. With every degree above norm, the neodymium's capacity temporarily lowers. Avoid using this product close to heaters higher than its working range. Ignoring the limit will lead to permanent loss of magnetic properties.

*Engineering note: Heat tolerance is determined by both grade, and the Permeance Coefficient Pc. Flat magnets (low permeance coefficient) risk losing magnetic properties under lower heat stress compared to rod magnets. Red status in the table points to a risk of irreversible loss for this particular item.

Table 6: Two magnets (attraction) - field range
MP 20x8/4x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Strength (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	9.28 kg / 20.47 LBS 4 012 Gs	1.39 kg / 3.07 LBS 1393 g / 13.7 N	N/A
1 mm	8.73 kg / 19.25 LBS 4 701 Gs	1.31 kg / 2.89 LBS 1310 g / 12.8 N	7.86 kg / 17.33 LBS ~0 Gs
2 mm	8.11 kg / 17.88 LBS 4 530 Gs	1.22 kg / 2.68 LBS 1216 g / 11.9 N	7.30 kg / 16.09 LBS ~0 Gs
3 mm	7.45 kg / 16.42 LBS 4 342 Gs	1.12 kg / 2.46 LBS 1117 g / 11.0 N	6.70 kg / 14.78 LBS ~0 Gs
5 mm	6.10 kg / 13.45 LBS 3 930 Gs	0.92 kg / 2.02 LBS 915 g / 9.0 N	5.49 kg / 12.11 LBS ~0 Gs
10 mm	3.27 kg / 7.20 LBS 2 875 Gs	0.49 kg / 1.08 LBS 490 g / 4.8 N	2.94 kg / 6.48 LBS ~0 Gs
20 mm	0.75 kg / 1.66 LBS 1 382 Gs	0.11 kg / 0.25 LBS 113 g / 1.1 N	0.68 kg / 1.50 LBS ~0 Gs
50 mm	0.02 kg / 0.04 LBS 220 Gs	0.00 kg / 0.01 LBS 3 g / 0.0 N	0.02 kg / 0.04 LBS ~0 Gs
60 mm	0.01 kg / 0.02 LBS 139 Gs	0.00 kg / 0.00 LBS 1 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
70 mm	0.00 kg / 0.01 LBS 93 Gs	0.00 kg / 0.00 LBS 1 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
80 mm	0.00 kg / 0.00 LBS 65 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 47 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 35 Gs	0.00 kg / 0.00 LBS 0 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs

Two magnets interact from a wider radius than a magnet and steel setup. Such a system of two magnets produces a massive flux and a larger range of performance. Want to build a solid fastener? Use a pair of magnets instead of one magnet and a steel. Exercise caution that when bringing together two magnets, the impact force is massive. The levitation is marginally weaker than the connection force, but still large.
*The magnetic induction between like poles reaches ~0 Gs in the exact middle between the magnets (resulting from vector opposition).
Attention: Figures demonstrate sliding force of dual same magnets (friction coefficient ~0.15 for Ni-Ni plating).

Table 7: Protective zones (electronics) - warnings
MP 20x8/4x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	8.0 cm
Hearing aid	10 Gs (1.0 mT)	6.5 cm
Timepiece	20 Gs (2.0 mT)	5.0 cm
Phone / Smartphone	40 Gs (4.0 mT)	4.0 cm
Remote	50 Gs (5.0 mT)	3.5 cm
Payment card	400 Gs (40.0 mT)	1.5 cm
HDD hard drive	600 Gs (60.0 mT)	1.5 cm

Extremely neodym field poses a real danger to IT equipment as well as medical implants. These NdFeB products generate a flux that disrupts operation of sensitive medical devices. Notice: the invisible magnetic field passes through tissues and plastic. Exceptional care must be exercised by people with hearing aids and insulin pumps. The risk also applies to: mechanical watches, car keys, speakers, and screens. Avoid contact with magnetic cards, hard drives, or precise measuring instruments.

Table 8: Dynamics (kinetic energy) - warning
MP 20x8/4x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	25.67 km/h (7.13 m/s)	0.29 J
30 mm	42.38 km/h (11.77 m/s)	0.78 J
50 mm	54.68 km/h (15.19 m/s)	1.30 J
100 mm	77.33 km/h (21.48 m/s)	2.61 J

Neodymium magnets are prone to chipping – a violent impact against metal causes immediate chipping. Watch the impact speed – a neodymium left loose speeds with massive force. Kinetic force can trigger coating fragments or injury to fingers. Be sure to control the product during mounting so it doesn't hit violently against the steel surface. A contact at a velocity of dozens of km/h almost guarantees destruction of the magnet. Use safety goggles when working with large magnets.

Table 9: Surface protection spec
MP 20x8/4x5 / 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)

Neodymium magnets are highly susceptible to corrosion without proper protection. Improper coating selection is the most common cause of magnet failure over time.

Table 10: Construction data (P_c)
MP 20x8/4x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	7 218 Mx	72.2 µWb
P_c Coefficient	0.31	Low (Flat)

Total magnetic flux passing through the pole surface. Essential parameter for generator designers and motors. P_c value determines the magnet's operating point.

Table 11: Physics of underwater searching
MP 20x8/4x5 / N38

Environment	Effective steel pull	Effect
Air (land)	6.65 kg	Standard
Water (riverbed)	7.61 kg (+0.96 kg buoyancy gain)	+14.5%

Warning: This magnet has a standard nickel coating. After use in water, it must be dried and maintained immediately, otherwise it will rust!

Water displaces steel, making heavy objects slightly lighter. Buoyancy helps in lifting finds.

1. Shear force

*Note: On a vertical surface, the magnet holds only ~20% of its nominal pull.

2. Plate thickness effect

*Thin metal sheet (e.g. computer case) significantly reduces 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 P_c (Permeance Coefficient) = 0.31

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 P_c (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 P_c 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

Chemical composition

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%

Sustainability

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: 030333-2026

Magnet Unit Converter

Magnet pull force

Kilograms (kg)

Newtons (N)

Pounds (lbs)

Magnetic Field

Induction (T)

Enter your figure in one of the inputs, and the rest convert instantly.

Check out also products

Product available Ships in 2 days

HH 20x7.2 [M4] / N38 - through hole magnetic holder

6.40 ZŁ brutto / pcs

Product available Ships in 2 days

MW 20x1.5 / N38 - cylindrical magnet

1.574 ZŁ brutto / pcs

Product available Ships in 2 days

SM 25x150 [2xM8] / N52 - magnetic separator

467.40 ZŁ brutto / pcs

Product available Ships in 2 days

UMS 25x10.5x5.5x8 / N38 - conical magnetic holder

9.72 ZŁ brutto / pcs

The ring magnet with a hole MP 20x8/4x5 / N38 is created for mechanical fastening, where glue might fail or be insufficient. Mounting is clean and reversible, unlike gluing. This product with a force of 6.65 kg works great as a door latch, speaker holder, or mounting element in devices.

This material behaves more like porcelain than steel, so it doesn't forgive mistakes during mounting. When tightening the screw, you must maintain great sensitivity. We recommend tightening manually with a screwdriver, not an impact driver, because too much pressure will cause the ring to crack. 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. Damage to the protective layer during assembly is the most common cause of rusting. If you must use it outside, paint it with anti-corrosion paint after mounting.

A screw or bolt with a thread diameter smaller than 8/4 mm fits this model. For magnets with a straight hole, a conical head can act like a wedge and burst the magnet. Aesthetic mounting requires selecting the appropriate head size.

This model is characterized by dimensions Ø20x5 mm and a weight of 11.31 g. The pulling force of this model is an impressive 6.65 kg, which translates to 65.21 N in newtons. The mounting hole diameter is precisely 8/4 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 Nd₂Fe₁₄B magnets.

Pros

Apart from their strong holding force, neodymium magnets have these key benefits:

They do not lose magnetism, even after nearly 10 years – the reduction in strength is only ~1% (according to tests),
Magnets perfectly defend themselves against loss of magnetization caused by foreign field sources,
A magnet with a metallic gold surface has better aesthetics,
Magnetic induction on the working part of the magnet turns out to be very high,
Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the form) even at high temperatures reaching 230°C or more...
Thanks to modularity in constructing and the capacity to customize to specific needs,
Huge importance in electronics industry – they are commonly used in data components, motor assemblies, medical equipment, and complex engineering applications.
Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Cons

Characteristics of disadvantages of neodymium magnets and proposals for their use:

They are fragile upon too strong impacts. To avoid cracks, it is worth protecting magnets in special housings. Such protection not only protects the magnet but also increases its resistance to damage
When exposed to high temperature, neodymium magnets suffer a drop in strength. Often, when the temperature exceeds 80°C, their strength 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
They oxidize in a humid environment - during use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
Due to limitations in producing nuts and complex shapes in magnets, we recommend using casing - magnetic mount.
Potential hazard related to microscopic parts of magnets can be dangerous, in case of ingestion, which is particularly important in the aspect of protecting the youngest. Additionally, tiny parts of these products are able to be problematic in diagnostics medical after entering the body.
Due to neodymium price, their price is higher than average,

Pull force analysis

Highest magnetic holding force – what affects it?

The force parameter is a result of laboratory testing performed under specific, ideal conditions:

using a sheet made of low-carbon steel, serving as a circuit closing element
whose thickness equals approx. 10 mm
with an ideally smooth touching surface
without the slightest clearance between the magnet and steel
under perpendicular force vector (90-degree angle)
at room temperature

Determinants of lifting force in real conditions

Holding efficiency is affected by specific conditions, such as (from most important):

Distance – existence of any layer (rust, dirt, air) acts as an insulator, which reduces capacity rapidly (even by 50% at 0.5 mm).
Force direction – note that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the nominal value.
Substrate thickness – to utilize 100% power, the steel must be adequately massive. Thin sheet limits the attraction force (the magnet "punches through" it).
Chemical composition of the base – low-carbon steel attracts best. Alloy steels decrease magnetic properties and holding force.
Smoothness – ideal contact is possible only on polished steel. Any scratches and bumps create air cushions, reducing force.
Thermal conditions – neodymium magnets have a sensitivity to temperature. When it is hot they lose power, and in frost gain strength (up to a certain limit).

Lifting capacity testing was carried out on plates with a smooth surface of suitable thickness, under perpendicular forces, in contrast under parallel forces the load capacity is reduced by as much as 5 times. Additionally, even a small distance between the magnet and the plate lowers the holding force.

Warnings

GPS and phone interference

Navigation devices and smartphones are highly sensitive to magnetism. Direct contact with a powerful NdFeB magnet can ruin the sensors in your phone.

Adults only

Product intended for adults. Tiny parts pose a choking risk, leading to intestinal necrosis. Keep away from kids and pets.

Danger to pacemakers

Warning for patients: Strong magnetic fields affect electronics. Maintain at least 30 cm distance or request help to handle the magnets.

Beware of splinters

Beware of splinters. Magnets can explode upon violent connection, launching shards into the air. We recommend safety glasses.

Finger safety

Watch your fingers. Two large magnets will join immediately with a force of several hundred kilograms, crushing everything in their path. Be careful!

Keep away from computers

Very strong magnetic fields can corrupt files on credit cards, hard drives, and storage devices. Keep a distance of at least 10 cm.

Handling rules

Exercise caution. Neodymium magnets attract from a long distance and connect with massive power, often quicker than you can move away.

Dust is flammable

Fire warning: Rare earth powder is explosive. Do not process magnets without safety gear as this risks ignition.

Skin irritation risks

Allergy Notice: The nickel-copper-nickel coating consists of nickel. If skin irritation appears, immediately stop working with magnets and use protective gear.

Do not overheat magnets

Standard neodymium magnets (grade N) lose power when the temperature surpasses 80°C. Damage is permanent.

Attention! Want to know more? Read our article: Why are neodymium magnets dangerous?

MP 20x8/4x5 / N38 - ring magnet

Product card - MP 20x8/4x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Physical analysis of the product - technical parameters

Table 1: Static force (force vs gap) - characteristics MP 20x8/4x5 / N38

Table 2: Slippage capacity (vertical surface) MP 20x8/4x5 / N38

Table 3: Wall mounting (shearing) - vertical pull MP 20x8/4x5 / N38

Table 4: Material efficiency (saturation) - sheet metal selection MP 20x8/4x5 / N38

Table 5: Thermal stability (material behavior) - resistance threshold MP 20x8/4x5 / N38

Table 6: Two magnets (attraction) - field range MP 20x8/4x5 / N38

Table 7: Protective zones (electronics) - warnings MP 20x8/4x5 / N38

Table 8: Dynamics (kinetic energy) - warning MP 20x8/4x5 / N38

Table 9: Surface protection spec MP 20x8/4x5 / N38

Table 10: Construction data (Pc) MP 20x8/4x5 / N38

Table 11: Physics of underwater searching MP 20x8/4x5 / N38

1. Shear force

2. Plate thickness effect

3. Power loss vs temp

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

Chemical composition

Sustainability

Magnet pull force

Magnetic Field

Check out also products

HH 20x7.2 [M4] / N38 - through hole magnetic holder

MW 20x1.5 / N38 - cylindrical magnet

SM 25x150 [2xM8] / N52 - magnetic separator

UMS 25x10.5x5.5x8 / N38 - conical magnetic holder

Advantages as well as disadvantages of Nd2Fe14B magnets.

Pros

Cons

Pull force analysis

Highest magnetic holding force – what affects it?

Determinants of lifting force in real conditions

Warnings

GPS and phone interference

Adults only

Danger to pacemakers

Beware of splinters

Finger safety

Keep away from computers

Handling rules

Dust is flammable

Skin irritation risks

Do not overheat magnets

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs gap) - characteristics
MP 20x8/4x5 / N38

Table 2: Slippage capacity (vertical surface)
MP 20x8/4x5 / N38

Table 3: Wall mounting (shearing) - vertical pull
MP 20x8/4x5 / N38

Table 4: Material efficiency (saturation) - sheet metal selection
MP 20x8/4x5 / N38

Table 5: Thermal stability (material behavior) - resistance threshold
MP 20x8/4x5 / N38

Table 6: Two magnets (attraction) - field range
MP 20x8/4x5 / N38

Table 7: Protective zones (electronics) - warnings
MP 20x8/4x5 / N38

Table 8: Dynamics (kinetic energy) - warning
MP 20x8/4x5 / N38

Table 9: Surface protection spec
MP 20x8/4x5 / N38

Table 10: Construction data (P_c)
MP 20x8/4x5 / N38

Table 11: Physics of underwater searching
MP 20x8/4x5 / N38

Advantages as well as disadvantages of Nd₂Fe₁₄B magnets.