Micro bearing refers to the bearings with outer diameter less than 9mm for  metric series ; for inch mini bearings  they are bearings which with outer diameter less than 9.525mm!

The main materials arebearing steel, stainless steel, plastic, ceramics, etc., now the small bearings with minimum inner diameter can be 0.6mm, and generally the inner diameter is 1mm.

Miniature bearings are applicable to various industrial equipment, small rotary motors and other fields with high speed and low noise, such as:

Office equipment, micro motors, instruments, laser engraving, small clocks, soft drives, pressure rotors, dental drills, hard disk motors, stepping motors, video recorders, magnetic drums, toy models, computer cooling fans, cash counters, fax machines and other related fields.

Below here are some common miniature ball bearings number for your reference :

682 682ZZ MR52 MR52ZZ 692 692ZZ 683 683ZZ MR83 MR83ZZ 693 693ZZ 603 603ZZ 623 623ZZ MR74 MR74ZZ MR84 MR84ZZ 684 684ZZ MR104 MR104ZZ 694 694ZZ 604 604ZZ 624 624ZZ MR85 MR85ZZ MR95 MR95ZZ MR105 MR105ZZ 685 685ZZ MR115ZZ 695ZZ 605ZZ 625ZZ MR106 MR106ZZ MR126 MR126ZZ 686 686ZZ 696ZZ 606ZZ 626ZZ MR117 MR117ZZ MR137 MR137ZZ 687 687ZZ 607ZZ 627ZZ MR128 M R128ZZ MR148 MR148ZZ 688 688ZZ 698ZZ 608ZZ MR149 MR149ZZ 689 689ZZ 609ZZ 629ZZ 639ZZ

MKL BEARINGS can produce 681 miniature bearings with dimension 1*3*1mm bearings .

We also can produce special dimension miniature bearings with 2.45*5*1.01mm

Here is miniature bearing size chart for your reference: