When it comes to black round magnet with hole, which kind of magnet comes to your mind, ferrite or neodymium magnet? The sample of this black magnet with holes (straight and screw holes) you are viewing now is made of rare earth neodymium material with strong magnetic force, and the black surface is black epoxy coated so it looks black as well, which is good protection for the magnet and suitable for use in harsher environments.
In the main picture product, there are 3 kinds of black round magnets with holes, they are black round magnets with small holes, black round magnets with large holes, black round magnets with countersunk holes, you can choose the one which is suitable for your project to buy.
About black round magnets for science;