Who is NMB Bearing?
NMB, namely Nippon Miniature Bearing Co., Ltd., was established in Japan in 1951. It is a specialized manufacturer of miniature precision ball bearings and small sized ball bearings with an outer diameter of or less than 30 mm. Nippon Miniature Bearing Co., Ltd changed its name into Minebea Co., Ltd in October 1981. And in 2017, Minebea Co., Ltd merged with Mitsumi Electric Co., Ltd, and changed its name to Minebea Mitsumi Co., Ltd.
Now, NMB is the world’s largest manufacturer of miniature precision ball bearings. It is also leading manufacturer of precision electro-mechanical components, including cooling fans and blowers, precision small motors, etc. Its high-precision miniature ball bearings are widely used in video recorders, air conditioners, vacuum cleaners, and automotive motors. transmission and other fields of medical equipment, and computer peripheral hardware, especially in high-speed and high-precision products.
Who is Fitrun Bearing?
Fitrun Bearing was founded in 2003 who is engaged in manufacturing miniature ball bearings with bore diameter of or less than 10 mm. With over 20 years development, it expands the product range and also manufactures ball bearings with bore diameter larger than 10 mm now.
It has 2 ISO9001:2015 certified ball bearing factories with a production capability over 35 million sets of miniature bearings annually, and the bearings are exported to more than 30 countries worldwide.
NMB Bearing Cross Reference Size Chart
Fitrun’s many models of miniature ball bearings have a potential interchange with NMB bearings. You will find the interchange information in the following NMB Bearing Cross Reference Charts for some of the models.
All the models listed in the charts are stainless steel ball bearings, they are also available in chrome steel which is relatively cost effective for lower requirement applications. If you could not find what you are looking for, please contact with us and we will find it for you. We provide free samples to you to test the compatibility before volume.
Metric Standard, Open Type
| Fitrun | NMB | Bore Dia | Outer Dia |
| S681 | DDL-310 | 1 mm | 3 mm |
| S681X | DDL-415 | 1.5 mm | 4 mm |
| S691X | DDR-515 | 1.5 mm | 5 mm |
| S682 | DDL-520 | 2 mm | 5 mm |
| SMR52 | DDL-520W02 | 2 mm | 5 mm |
| S692 | DDR-620 | 2 mm | 6 mm |
| SMR62 | DDR-620W52 | 2 mm | 6 mm |
| SMR72 | DDR-720Y52 | 2 mm | 7 mm |
| S602 | DDR-720 | 2 mm | 7 mm |
| S682X | DDL-625 | 2.5 mm | 6 mm |
| S692X | DDR-725 | 2.5 mm | 7 mm |
| S602X | DDR-825 | 2.5 mm | 8 mm |
| SMR63 | DDL-630 | 3 mm | 6 mm |
| S683 | DDL-730 | 3 mm | 7 mm |
| S693 | DDR-830 | 3 mm | 8 mm |
| SMR93 | DDR-930Y52 | 3 mm | 9 mm |
| S603 | DDR-930 | 3 mm | 9 mm |
| S623 | DDR-1030 | 3 mm | 10 mm |
| SMR74 | DDL-740 | 4 mm | 7 mm |
| SMR84 | DDL-840 | 4 mm | 8 mm |
| S684 | DDL-940 | 4 mm | 9 mm |
| SMR104 | DDL-1040 | 4 mm | 10 mm |
| S694 | DDR-1140 | 4 mm | 11 mm |
| S604 | DDR-1240 | 4 mm | 12 mm |
| S624 | DDR-1340 | 4 mm | 13 mm |
| SMR85 | DDL-850 | 5 mm | 8 mm |
| SMR95 | DDL-950 | 5 mm | 9 mm |
| SMR105 | DDL-1050 | 5 mm | 10 mm |
| S685 | DDL-1150 | 5 mm | 11 mm |
| S695 | DDR-1350 | 5 mm | 13 mm |
| S605 | DDR-1450 | 5 mm | 14 mm |
| SMR106 | DDL-1060 | 6 mm | 10 mm |
| SMR126 | DDL-1260 | 6 mm | 12 mm |
| S686 | DDL-1360 | 6 mm | 13 mm |
| S696 | DDR-1560 | 6 mm | 15 mm |
| SMR117 | DDL-1170 | 7 mm | 11 mm |
| SMR137 | DDL-1370 | 7 mm | 13 mm |
| S687 | DDL-1470 | 7 mm | 14 mm |
| SMR128 | DDL-1280 | 8 mm | 12 mm |
| SMR148 | DDL-1480 | 8 mm | 14 mm |
| S688 | DDL-1680 | 8 mm | 16 mm |
| S689 | DDL-1790 | 9 mm | 17 mm |
Metric Standard, Double Shielded
| Fitrun | NMB | Bore Dia | Outer Dia |
| S681XZZ | DDL-415ZZ | 1.5 mm | 4 mm |
| S691XZZ | DDR-515ZZ | 1.5 mm | 5 mm |
| S682ZZ | DDL-520ZZ | 2 mm | 5 mm |
| SMR52ZZ | DDL-520W02ZZ | 2 mm | 5 mm |
| S692ZZ | DDR-620ZZ | 2 mm | 6 mm |
| SMR62ZZ | DDR-620W52ZZ | 2 mm | 6 mm |
| SMR72ZZ | DDR-720Y52ZZ | 2 mm | 7 mm |
| S602ZZ | DDR-720ZZ | 2 mm | 7 mm |
| S682XZZ | DDL-625ZZ | 2.5 mm | 6 mm |
| S692XZZ | DDR-725ZZ | 2.5 mm | 7 mm |
| SMR63ZZ | DDL-630ZZ | 3 mm | 6 mm |
| S683ZZ | DDL-730ZZ | 3 mm | 7 mm |
| S693ZZ | DDR-830ZZ | 3 mm | 8 mm |
| SMR93ZZ | DDR-930Y52ZZ | 3 mm | 9 mm |
| S623ZZ | DDR-1030ZZ | 3 mm | 10 mm |
| SMR74ZZ | DDL-740ZZ | 4 mm | 7 mm |
| SMR84ZZ | DDL-840ZZ | 4 mm | 8 mm |
| S684ZZ | DDL-940ZZ | 4 mm | 9 mm |
| SMR104ZZ | DDL-1040ZZ | 4 mm | 10 mm |
| S694ZZ | DDR-1140ZZ | 4 mm | 11 mm |
| S604ZZ | DDR-1240ZZ | 4 mm | 12 mm |
| S624ZZ | DDR-1340ZZ | 4 mm | 13 mm |
| SMR85ZZ | DDL-850ZZ | 5 mm | 8 mm |
| SMR95ZZ | DDL-950ZZ | 5 mm | 9 mm |
| SMR105ZZ | DDL-1050ZZ | 5 mm | 10 mm |
| SMR115ZZ | DDL-1150Y04ZZ | 5 mm | 11 mm |
| S685ZZ | DDL-1150ZZ | 5 mm | 11 mm |
| S695ZZ | DDR-1350ZZ | 5 mm | 13 mm |
| S605ZZ | DDR-1450ZZ | 5 mm | 14 mm |
| SMR106ZZ | DDL-1060ZZ | 6 mm | 10 mm |
| SMR126ZZ | DDL-1260ZZ | 6 mm | 12 mm |
| S686ZZ | DDL-1360ZZ | 6 mm | 13 mm |
| S696ZZ | DDR-1560ZZ | 6 mm | 15 mm |
| SMR117ZZ | DDL-1170ZZ | 7 mm | 11 mm |
| SMR137ZZ | DDL-1370ZZ | 7 mm | 13 mm |
| S687ZZ | DDL-1470ZZ | 7 mm | 14 mm |
| SMR128ZZ | DDL-1280ZZ | 8 mm | 12 mm |
| SMR148ZZ | DDL-1480ZZ | 8 mm | 14 mm |
| S688ZZ | DDL-1680ZZ | 8 mm | 16 mm |
| S689ZZ | DDL-1790ZZ | 9 mm | 17 mm |
Metric Flanged, Open Type
| Fitrun | NMB | Bore Dia | Outer Dia |
| SF681X | DDLF-415 | 1.5 mm | 4 mm |
| SF691X | DDRF-515 | 1.5 mm | 5 mm |
| SF682 | DDLF-520 | 2 mm | 5 mm |
| SMF52 | DDLF-520WO2 | 2 mm | 5 mm |
| SF692 | DDRF-620 | 2 mm | 6 mm |
| SMF72 | DDRF-720Y52 | 2 mm | 7 mm |
| SF682X | DDLF-625 | 2.5 mm | 6 mm |
| SF692X | DDRF-725 | 2.5 mm | 7 mm |
| SF602X | DDRF-825 | 2.5 mm | 8 mm |
| SMF63 | DDLF-630 | 3 mm | 6 mm |
| SF683 | DDLF-730 | 3 mm | 7 mm |
| SF693 | DDRF-830 | 3 mm | 8 mm |
| SMF93 | DDRF-930Y52 | 3 mm | 9 mm |
| SF623 | DDRF-1030 | 3 mm | 10 mm |
| SMF74 | DDLF-740 | 4 mm | 7 mm |
| SMF84 | DDLF-840 | 4 mm | 8 mm |
| SF684 | DDLF-940 | 4 mm | 9 mm |
| SMF104 | DDLF-1040 | 4 mm | 10 mm |
| SF694 | DDRF-1140 | 4 mm | 11 mm |
| SF604 | DDRF-1240 | 4 mm | 12 mm |
| SF624 | DDRF-1340 | 4 mm | 13 mm |
| SMF85 | DDLR850 | 5 mm | 8 mm |
| SMF95 | DDLF-950 | 5 mm | 9 mm |
| SMF105 | DDLF-1050 | 5 mm | 10 mm |
| SF685 | DDLF-1150 | 5 mm | 11 mm |
| SF695 | DDRF-1350 | 5 mm | 13 mm |
| SF605 | DDRF-1450 | 5 mm | 14 mm |
| SMF106 | DDLF-1060 | 6 mm | 10 mm |
| SMF126 | DDLF-1260 | 6 mm | 12 mm |
| SF686 | DDLF-1360 | 6 mm | 13 mm |
| SF696 | DDRF-1560 | 6 mm | 15 mm |
| SMF117 | DDLF-1170 | 7 mm | 11 mm |
| SMF137 | DDLF-1370 | 7 mm | 13 mm |
| SF687 | DDLF-1470 | 7 mm | 14 mm |
| SMF128 | DDLF-1280 | 8 mm | 12 mm |
| SMF148 | DDLF-1480 | 8 mm | 14 mm |
| SF688 | DDLF-1680 | 8 mm | 16 mm |
| SF689 | DDLF-1790 | 9 mm | 17 mm |
Metric Flanged, Double Shielded
| Fitrun | NMB | Bore Dia | Outer Dia |
| SF681XZZ | DDLF-415ZZ | 1.5 mm | 4 mm |
| SF691XZZ | DDRF-515ZZ | 1.5 mm | 5 mm |
| SF682ZZ | DDLF-520ZZ | 2 mm | 5 mm |
| SMF52ZZ | DDLF-520WO2ZZ | 2 mm | 5 mm |
| SF692ZZ | DDRF-620ZZ | 2 mm | 6 mm |
| SMF72ZZ | DDRF-720Y52ZZ | 2 mm | 7 mm |
| SF602ZZ | DDRF-720ZZ | 2 mm | 7 mm |
| SF682XZZ | DDLF-625ZZ | 2.5 mm | 6 mm |
| SF692XZZ | DDRF-725ZZ | 2.5 mm | 7 mm |
| SF602XZZ | DDRF-825ZZ | 2.5 mm | 8 mm |
| SMF63ZZ | DDLF-630ZZ | 3 mm | 6 mm |
| SF683ZZ | DDLF-730ZZ | 3 mm | 7 mm |
| SF693ZZ | DDRF-830ZZ | 3 mm | 8 mm |
| SMF93ZZ | DDRF-930Y52ZZ | 3 mm | 9 mm |
| SF623ZZ | DDRF-1030ZZ | 3 mm | 10 mm |
| SMF74ZZ | DDLF-740ZZ | 4 mm | 7 mm |
| SMF84ZZ | DDLF-840ZZ | 4 mm | 8 mm |
| SF684ZZ | DDLF-940ZZ | 4 mm | 9 mm |
| SMF104ZZ | DDLF-1040ZZ | 4 mm | 10 mm |
| SF694ZZ | DDRF-1140ZZ | 4 mm | 11 mm |
| SF604ZZ | DDRF-1240ZZ | 4 mm | 12 mm |
| SF624ZZ | DDRF-1340ZZ | 4 mm | 13 mm |
| SMF85ZZ | DDLR850ZZ | 5 mm | 8 mm |
| SMF95ZZ | DDLF-950ZZ | 5 mm | 9 mm |
| SMF105ZZ | DDLF-1050ZZ | 5 mm | 10 mm |
| SF685ZZ | DDLF-1150ZZ | 5 mm | 11 mm |
| SF695ZZ | DDRF-1350ZZ | 5 mm | 13 mm |
| SF605ZZ | DDRF-1450ZZ | 5 mm | 14 mm |
| SMF106ZZ | DDLF-1060ZZ | 6 mm | 10 mm |
| SMF126ZZ | DDLF-1260ZZ | 6 mm | 12 mm |
| SF686ZZ | DDLF-1360ZZ | 6 mm | 13 mm |
| SF696ZZ | DDRF-1560ZZ | 6 mm | 15 mm |
| SMF117ZZ | DDLF-1170ZZ | 7 mm | 11 mm |
| SMF137ZZ | DDLF-1370ZZ | 7 mm | 13 mm |
| SF687ZZ | DDLF-1470ZZ | 7 mm | 14 mm |
| SMF128ZZ | DDLF-1280ZZ | 8 mm | 12 mm |
| SMF148ZZ | DDLF-1480ZZ | 8 mm | 14 mm |
| SF688ZZ | DDLF-1680ZZ | 8 mm | 16 mm |
| SF689ZZ | DDLF-1790ZZ | 9 mm | 17 mm |
Inch Standard, Open Type
| Fitrun | NMB | Bore Dia | Outer Dia |
| SR09 | DDRI-2 | 0.04″ | 0.125″ |
| SR0 | DDRI-21/2 | 0.04688″ | 0.15625″ |
| SR1 | DDRI-3 | 0.05556″ | 0.1875″ |
| SR1-4 | DDRI-4 | 0.07813″ | 0.25″ |
| SR1-5 | DDRI-5 | 0.09375″ | 0.3125″ |
| SR133 | DDRI-3332 | 0.09375″ | 0.1875″ |
| SR144 | DDRI-418 | 0.125″ | 0.25″ |
| SR2 | DDR-2 | 0.125″ | 0.375″ |
| SR2-5 | DDRI-518 | 0.125″ | 0.3125″ |
| SR2-6 | DDRI-618 | 0.125″ | 0.375″ |
| SR2A | DDR-2A | 0.125″ | 0.5″ |
| SR155 | DDRI-5532 | 0.15625″ | 0.3125″ |
| SR156 | DDRI-5632 | 0.1875″ | 0.3125″ |
| SR166 | DDRI-6632 | 0.1875″ | 0.375″ |
| SR3 | DDR-3 | 0.1875″ | 0.5″ |
| SR168 | DDRI-614 | 0.25″ | 0.375″ |
| SR188 | DDRI-814 | 0.25″ | 0.5″ |
| SR4 | DDR-4 | 0.25″ | 0.625″ |
Inch Standard, Double Shielded
| Fitrun | NMB | Bore Dia | Outer Dia |
| SR0ZZ | DDRI-21/2ZZ | 0.04688″ | 0.15625″ |
| SR1ZZ | DDRI-3ZZ | 0.05556″ | 0.1875″ |
| SR1-4ZZ | DDRI-4ZZ | 0.07813″ | 0.25″ |
| SR133ZZ | DDRI-3332ZZ | 0.09375″ | 0.1875″ |
| SR1-5ZZ | DDRI-5ZZ | 0.09375″ | 0.3125″ |
| SR2ZZ | DDR-2ZZ | 0.125″ | 0.375″ |
| SR2-6ZZ | DDRI-618ZZ | 0.125″ | 0.375″ |
| SR2AZZ | SR2ACHH | 0.125″ | 0.5″ |
| SR155ZZ | DDRI-5532ZZ | 0.15625″ | 0.3125″ |
| SR156ZZ | DDRI-5632ZZ | 0.1875″ | 0.3125″ |
| SR166ZZ | DDRI-6632ZZ | 0.1875″ | 0.375″ |
| SR3ZZ | DDR-3ZZ | 0.1875″ | 0.5″ |
| SR168ZZ | DDRI-614ZZ | 0.25″ | 0.375″ |
| SR188ZZ | DDRI-814ZZ | 0.25″ | 0.5″ |
| SR4ZZ | DDR-4ZZ | 0.25″ | 0.625″ |
Inch Flanged, Open Type
| Fitrun | NMB | Bore Dia | Outer Dia |
| SFR0 | DDRIF-21/2 | 0.04688″ | 0.15625″ |
| SFR1 | DDRIF-3 | 0.05556″ | 0.1875″ |
| SFR1-4 | DDRIF-4 | 0.07813″ | 0.25″ |
| SFR1-5 | DDRIF-5 | 0.09375″ | 0.3125″ |
| SFR133 | DDRIF-3332 | 0.09375″ | 0.1875″ |
| SFR144 | DDRIF-418 | 0.125″ | 0.25″ |
| SFR2 | DDRF-2 | 0.125″ | 0.375″ |
| SFR2-5 | DDRIF-518 | 0.125″ | 0.3125″ |
| SFR2-6 | DDRIF-618 | 0.125″ | 0.375″ |
| SFR155 | DDRIF-5532 | 0.15625″ | 0.3125″ |
| SFR156 | DDRIF-5632 | 0.1875″ | 0.3125″ |
| SFR166 | DDRIF-6632 | 0.1875″ | 0.375″ |
| SFR3 | DDRF-3 | 0.1875″ | 0.5″ |
| SFR168 | DDRIF-614 | 0.25″ | 0.375″ |
| SFR188 | DDRIF-814 | 0.25″ | 0.5″ |
| SFR4 | DDRF-4 | 0.25″ | 0.625″ |
Inch Flanged, Double Shielded
| Fitrun | NMB | Bore Dia | Outer Dia |
| SFR0ZZ | DDRIF-21/2ZZ | 0.04688″ | 0.15625″ |
| SFR1ZZ | DDRIF-3ZZ | 0.05556″ | 0.1875″ |
| SFR1-4ZZ | DDRIF-4ZZ | 0.07813″ | 0.25″ |
| SFR133ZZ | DDRIF-3332ZZ | 0.09375″ | 0.1875″ |
| SFR1-5ZZ | DDRIF-5ZZ | 0.09375″ | 0.3125″ |
| SFR2ZZ | DDRF-2ZZ | 0.125″ | 0.375″ |
| SFR2-6ZZ | DDRIF-618SS | 0.125″ | 0.375″ |
| SFR155ZZ | DDRIF-5532ZZ | 0.15625″ | 0.3125″ |
| SFR156ZZ | DDRIF-5632ZZ | 0.1875″ | 0.3125″ |
| SFR166ZZ | DDRIF-6632ZZ | 0.1875″ | 0.375″ |
| SFR3ZZ | DDRF-3ZZ | 0.1875″ | 0.5″ |
| SFR168ZZ | DDRIF-614ZZ | 0.25″ | 0.375″ |
| SFR188ZZ | DDRIF-814ZZ | 0.25″ | 0.5″ |
| SFR4ZZ | DDRF-4ZZ | 0.25″ | 0.625″ |