What is the strongest type of permanent magnet commercially available?

I love these magnets, they are typically on the small side but super strong, can actually be difficult to remove them.

Wonderfully made. Extremely strong. Papers won't fall off of the fridge with these babies. 😃

Where are bonded NdFeB magnets produced?

I’m always suspicious when a product with a really complicated or unusual formula is developed independently by two companies at the same time