Fix the countersunk hole with rose and attach the product to an iron door or iron, or two pairs.

1, the temperature   When selecting ndfeb magnet, the client should choose the appropriate magnetic label according to its working temperature. If the working temperature is higher than the bearing temperature of the magnetic label, the magnet will slowly degauss until it is not magnetized. Be sure to confirm the working temperature and the license plate number suitable for your own use before ordering. 
2, environmental   If use the magnet device in sealed condition, can consider to choose the surface plating or white zinc plated magnets, so we can save the cost, if the magnet is exposed to damp air, salt spray conditions, in particular, consider nickel plating surface treatment of the magnet. Magnets should be stored in a dry, thermostatic environment, separated and wrapped with plastic, wood chips, cardboard, foam, etc. Keep away from iron objects and magnetized objects such as monitors, bank CARDS, computers, televisions, mobile phones, etc. 
3. User objects   As for environmental protection, for relatively developed countries, such as North America and Europe, users should pay special attention to environmental protection matters, and export use must pass the six eu standards of SGS. For users in China or some less developed countries, environmental protection requirements are not considered. 
 4. Handling and stacking     Ndfeb strong magnetic materials, hard, brittle, strong magnetic field, to light (especially the large size and thin), the only, when a strong magnet itself or with any other iron absorption or separation, careful operation impact. Otherwise, it may damage the magnet or splint finger due to collision. Because ndfeb is a polymetallic alloy material with a density of 7.45, it has a heavy and brittle nature. So you have to be very careful when you move it around so that it doesn't break. Storage should also keep the environment dry, do not stack directly on the ground, it is best to pad cardboard or place on the shelf.   
5. Instructions for use     It is recommended to push the magnets apart when they are attracted to each other. Fix the whole magnet with your left hand. With your right hand, use your index finger and thumb to cooperate. Remove the magnet horizontally. Keep it light and away from the iron or magnetic objects (about 16 cm) or wrap it in paper to make it safe. If you need to put the magnet back into the whole magnet, please slowly put it back and move it in close to the edge. The hand must hold the magnet until it has moved in.
Customers need to know the following things before purchasing ndfeb magnet:         
I. this kind of magnet sold by yiwu hao magnetic material factory belongs to ndfeb rare earth permanent magnet, all of which belong to strong magnet, and it is the magnet with the highest commercialization performance found at present. The best and strongest magnetic materials are well - deserved strong magnetism. It is called \"magnetic king\" because of its excellent magnetic energy. Please be assured to buy it and use it carefully.         
 2. Our company's specifications are round, square, circular, shaped, trapezoid, tile, spherical, irregular figures and other ndfeb strong magnets, which can be customized for production. All sizes of magnets in our specifications are in millimetres.        
     【 1 】 generally expressed in D diameter circular size (due to belong to the special symbol for the convenience of the majority to use D instead of Φ), such as D10X1MM represents is 10 mm in diameter, 1 mm is the thickness of the magnet. X is the mathematical symbol for multiplication.        
     [2] the size of a square is X long, X wide and X high. Such as F50x25x13MM, said is square magnet is 50 mm long, wide is 25 mm, thickness is 13 mm, usually the default last a digital representation of the square magnet magnetization direction, such as F50x25x13 squares, magnetization direction is the direction of the 13 mm, is also highly direction of magnetization. NS is on the two largest sides, which is the 50x25 side.        
     [3] the size of the ring is denoted by the outer diameter DX and the inner diameter DX height. For example, D32XD18X6 ring magnet, denotes the outer diameter of 32 mm, the inner diameter of 18 mm, and the height of 6 mm. Height is also called thickness. At present, the ring is also divided into a straight hole and a countersunk hole. The hole of a straight hole is punched in vertically, while the countersunk hole is divided into a large hole and a small hole. 
Iii. Our company can produce a variety of brand ndfeb magnets as follows:
       N35 N38 N40 N42 N45 N48 N50 N52                     Maximum operating temperature 80 degrees   
           35 m. 38 m. 40 m 42 m. 45 m. 48 m 50 m.                         Maximum operating temperature 100 degrees   
           33 h 35 h 38 h 40 h 42 h 45 h 48 h.                         Maximum operating temperature: 120 degrees   
           30SH 33SH 35SH 38SH 40SH 42SH                               Maximum operating temperature 150 degrees   
           30UH 33UH 35UH 38UH 40UH                                 Maximum operating temperature 180 degrees   
           30 eh eh eh eh 38 35 33                                   Maximum operating temperature: 200 degrees                                 30 35 33 ah ah ah                                     Maximum operating temperature 230 degrees    
33, 35, 38, 40, 42, etc. represent the maximum magnetic energy product. The maximum magnetic energy of N33 ndfeb is about 33MGOe. The maximum magnetic energy of N35 ndfeb material is about 35MGOe. The maximum magnetic energy of ndfeb N40 is about 40MGOe. The conversion between MGOe and kA/m3 is 1MGOe = 8kA/m3, which means the maximum magnetic energy product of N40 is about 320kA/m3.      
The higher the brand number, the stronger the magnetism, the higher the corresponding price, so specific needs to be determined according to the actual needs of customers. In general, such as packaging, machinery, stationery and other less demanding products are mainly n33 brand. Most of the low - and medium-grade loudspeakers use n35 brand magnets.        
Sintered ndfeb magnet, with unimaginable super magnetic force, the sintered ndfeb magnet in theory has a maximum suction of hundreds of times its own weight and is the most powerful permanent magnet at present. Of course, the bigger the magnet, the stronger the magnetic force.         If you need to customize, please contact our customer service to explain the size, brand number, quantity, electroplating layer, tolerance requirement, magnetic direction and so on. We will produce according to your requirement.