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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Moped Scooter Reed Valve Block For Yamaha RS125 RXK 125cc 2 Stroke Motorcycle Reed Valves With Petals Membran Assy Engine Parts
Aliexpress UK
N52 magnets, strong neodymium block magnet, 28x5x2 mm magnet, rectangle rare earth magnet, super strong N52 neodymium, DIY magnet, engineering magnet, craft magnet, neodymium strip magnet, powerful mini magnet, magnetic fixing solutions.
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Garden Tool Parts Accessories Chainsaw Attachment 5200 Tower Spring and Chain Block
Aliexpress UK
They are also available with the north pole on the non-adhesive side. Coated with three layers of nickel, copper and nickel to reduce corrosion and provide a smooth finish.
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Gasonline Engine 3.0L 6 Cylinders CRE CTD For Audi A6 A7 Q7 Long Cylinder Block Auto Engine Parts
Aliexpress UK
These large, thin rectangular neodymium magnets are axially magnetised between the two 130mm x 8mm rectangular faces and provide an incredible pull of 23.7kg. Each magnet is coated with three layers of nickel, copper and nickel to give superior corrosion resistance and provide a smooth and clean finish.
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50/100/200# Cylindrical grinding wheel Metal Polishing Block M10 Threaded Grinder Rotating Tools Accessories Sharpening Stone
Aliexpress UK
Grade: N50. Super strong rare earth magnet. Hole: approx. Due to differences in lighting and screens, the color of the product may be slightly different from the picture. Perfect for sticking notes on fridge doors.
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Unipolar Splitter Junction Box 1 In 12/14/15/16 Out Retardant Metering Cabinet Wire Terminal Block Retardant Flame Retar Parts
Aliexpress UK
40x20x10 mm (N52) Neodymium Magnet. Neodymium is about as common as tin or lead. There are two types of “Rare Earth Magnets” SMCO (Samarium-Cobalt) and Neodymium. Neodymium are the magnetically stronger and cheaper of the two but are more susceptible to oxidation, this is why they are protected by Nickel plating.
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Mould King Technology Parts Power Motor M L XL Servo Motor 4.0 6.0 Remote Control for MOC Electric Building Blocks Modification
Aliexpress UK
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. They are strong enough that they can fly into each other or to a piece of iron or steel with such velocity that they can break and send sharp 'shrapnel' flying about!
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Do Not Block Drive Aluminum Metal Warning Sign Uvresistance Waterproof Easy To Install For House And Business 12"X16" sign sign
Aliexpress UK
These thin rectangular neodymium magnets are axially magnetised between the two 20mm x 4mm rectangular faces and provide a maximum pull of 1.92kg. Every magnet is coated with three layers of nickel, copper and nickel to reduce corrosion and provide a smooth finish.
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Abrasive Cleaning Eraser Stick Sandpaper Cleaner Natural Rubber Cleaning Block Sandpaper Belts for Sanding Discs Sandpaper Belts
Aliexpress UK