Country - The bearings are not ABEC rated. They are however, built to Schumacher specs and are really darned nice.
Here is a bit of bearing info that applies to this question...
High ABEC rated bearings have tight tolerances. The better the rating the tighter the tolerances and the better the internal surface finishes are. This is good and bad. When new can clean expensive ABEC bearings are great. Unfortunatly after a few runs they can get dirty and the tight tolerances work against you. It is much more important to keep a high grade bearing clean in order for it to be free.
Starting with the Mi2EC Schumacher has been buying bearings built to thier specs. They have slightly looser tolerances but very fine surface finishes on the bearing races and very good quality balls. They also come oiled, not greased, so they are free and fast right out of the box.
The kit bearings are so good most of the factory team drivers use the stock bearings.
If you want the best possible bearings for you Mi3 the Schumacher Ceramic bearing set uses the same inner and outer races at the kit bearings but use silicon nitride ceramic balls for ultimate smoothness and durability.