They have a high magnetic field strength and have a high coercivity (which makes them magnetically stable). Usually surprise is an issue--they can jump out of your hands and snap together from a surprising distance before you realize what is happening.
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20 Pcs Small Round Magnet 5x8 Magnet 5mm X 8mm Permanent Super Strong Powerful Magnets 5*8 for Fridge, DIY, Building, Scientific
Aliexpress UK
N52 Neodymium disc Fasteners. Small & Tiny 2mm 3mm 4mm 5mm 10mm 20mm rare earth. Important Safety Notice: Due to their powerful magnetic properties, these fasteners must be handled with care. They arenot toys.
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10x5x2mm Magnets 10mm x 5mm X 2mm block Refrigerator magnets Imanes 10*5*2mm new maget
Aliexpress UK
Samarium Cobalt. Grade: N35. Neodymium Blocks. Neodymium Disks / Rods. Neodymium Cubes. Neodymium Rings. Neodymium Spheres. Neodymium - Self Adhesive.
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58x8.9x2.5mm Long Bar Magnets, Super Magnets Heavy Duty with Double-Sided Adhesive, Perfect For kitchens, handicrafts, and photo
Aliexpress UK
These magnets provide the strongest magnetic force for their size. Strong Neodymium Magnets - 2mm to 30mm Round Disc Magnets - N52 Grade. Choose from a variety of sizes, from small 2mm discs for crafting and DIY projects to larger 30mm discs for more demanding tasks.
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8x1.5mm Powerful Neodymium Magnet N35 NdfeB Permanent Magnetic imanes Round Super Strong Fridge Magnets
Aliexpress UK
When magnetising two Neodymium magnets together, safely slide magnets together to avoid high impacts. These magnets are incredibly strong and never fail to impress. The magnets are coated in four layers of Nickel, Copper and Boron to enhance the lifespan of the magnet and the coating also provides a smooth finish.
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8x1.5mm Powerful Neodymium Magnet N35 NdfeB Permanent Magnetic imanes Round Super Strong Fridge Magnets DIY
Aliexpress UK
These magnets are triple coated nickel-copper-nickel for good corrosion resistance and these magnets are magnetised axially giving a north pole on one flat face and a south pole on the opposite face.
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4x5 Powerful Magnets Disc 4mm x 5mm Small Round Magnet 4x5mm For Home Refrigerators, Offices DIY 4*5
Aliexpress UK
Neodymium magnets are an alloy of neodymium iron and boron. They have very high energy and are more powerful for their size than any other magnet material. You will find them in many industrial and household products and are ideal for crafting.
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5x2mm Round Durable Super Strong Magnet 5mm X 2mm N35 Permanent NdFeB 5*2 Powerful Magnetic Disc imanes Refrigerator Magnet
Aliexpress UK
N52 Neodymium disc magnets. High-Quality N52 Magnets – Sizes Ranging from 2mm to 40mm. Unmatched Strength with N52 Grade. With a maximum energy product of 52 MGOe, these magnets provide the highest level of magnetism, making them ideal for various applications requiring intense magnetic force.
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Super Powerful Magnets Neodymium Magnet NdfeB N35 Strong Permanent Magnetic Imanes Refrigerator Magnet 25x2/3/5mm 30x2/3/5mm
Aliexpress UK