This is a plastic wrapped magnet, the plastic is polystyrene plastic + ceramic ferrite round, diameter 25mm, overall thickness of 7mm, can be done in a variety of colors, packaging can be inserted card, suction card, boxed or bagged, suitable for teaching presentations, office, if you need to buy in bulk to consult the preferential price, please contact us to say your stated requirements.
You may be looking for something like the following;