High-performance magnets (such as high-grade neodymium iron boron) are inherently brittle and hard, resembling fragile glass. Magnetizing them is even more troublesome. The magnetic force is instantly fully charged, and the drastic changes in the magnetic field during magnetizing can induce stress inside the magnet, inherently posing a risk of cracking. After magnetizing, adjacent magnets can also "magnetically adhere crazily", easily causing chipping and falling off at the touch, leading to direct scrap. Adding a spacer can perfectly isolate and buffer the impact force of adhesion, avoiding collision damage. However, if the magnet specification is particularly small and the spacer is larger than it, it is naturally impossible to add.

After being magnetized, high-performance magnets are so strong that they can be firmly attracted together. When manually handled, it takes considerable effort to separate them, and excessive force may even break the magnets; during sorting on automated production lines, efficiency can also be delayed due to misalignment of attraction. Spacers can create gaps between magnets, making it easy to separate them, whether handled manually or by robotic arms, saving time and effort. However, for extremely small magnets, there is no space for spacers, and special processes must be employed to circumvent the handling challenges.

Lastly, it's worth emphasizing that while adding shims is beneficial, it's crucial to consider the magnet specifications. If the magnet specifications are particularly small (such as micro magnets measuring just a few millimeters), the size of the shims simply cannot match. Forcing a fit will not only affect the use of the magnet but may also damage the magnet itself. Therefore, manufacturers will flexibly adjust according to the magnet specifications, and only high-performance magnets with suitable specifications will be equipped with shims, balancing protection, convenience, and usage effectiveness.