These are small rare earth magnets - 0.25" cubed. Composed of Neodymium/Iron/Boron (NdFeB), these magnets are curiously strong and make for a great way to attach tools to a metal workbench, hold small children to a fridge, and as a trigger for reed switches. Activates the reed switch (shown below) at a distance of about 3cm. Sold in single units. https://elecena.pl/product/633816/magnet-square-0-25 2008-04-21 https://elecena.pl/product/633816/magnet-square-0-25 2008-09-23 https://elecena.pl/product/633816/magnet-square-0-25 2008-10-18 https://elecena.pl/product/633816/magnet-square-0-25 2016-11-25 https://elecena.pl/product/633816/magnet-square-0-25 2016-11-28 https://elecena.pl/product/633816/magnet-square-0-25 2016-11-30 https://elecena.pl/product/633816/magnet-square-0-25 2016-12-09 https://elecena.pl/product/633816/magnet-square-0-25 2016-12-13 https://elecena.pl/product/633816/magnet-square-0-25 2017-11-24 https://elecena.pl/product/633816/magnet-square-0-25 2017-11-28 https://elecena.pl/product/633816/magnet-square-0-25 2018-05-05 https://elecena.pl/product/633816/magnet-square-0-25 2018-11-21 https://elecena.pl/product/633816/magnet-square-0-25 2018-11-27 https://elecena.pl/product/633816/magnet-square-0-25 2022-02-22 https://elecena.pl/product/633816/magnet-square-0-25 2025-04-11 https://elecena.pl/product/633816/magnet-square-0-25 2025-04-14