Remanence Br is a measurement for the magnetic induction or magnetic flux density that, after successful magnetisation, remains in the magnet.
Simply said: the higher this value is, the "stronger" the magnet.
T (Tesla) is used as the unit of measurement for magnetic induction and, respectively, magnetic flux density.
The unit of measurement previously used was G (Gauss).
1 Tesla = 10 000 Gauss.
You can see the remanence of our super magnets in this table.
Difference to iron
If you removed an external magnetic field from a piece of iron, most of its molecules would return to their old positions and the iron would remain only slightly magnetic.
Thanks to its special crystal structure, the neodymium iron boron alloy, however, keeps a large part of its magnetisation indefinitely.