MR137-ZZ Micro Deep Groove Ball Bearing For Precision Instruments & Small Mechanisms | 7×13×3 Mm
The MR137-ZZ is a Miniature Double-Shielded Deep Groove Ball Bearing engineered for reliable performance in compact, precision applications. Utilizing the fundamental deep groove design, this small-diameter bearing is capable of supporting radial loads and very light axial loads in either direction. With a 7 mm bore and integrated double metal shields (ZZ) for basic contamination protection, it is an essential component for sensitive instruments, small motors, precision drives, and other applications where space is limited and smooth, low-friction operation is critical.
MR137-ZZ Deep Groove Ball Bearing 7×13×3 mm | Miniature Series | Double Metal Shields (ZZ)
A versatile and compact miniature-series bearing, built on the standard deep groove raceway geometry. It supports quiet, precise operation at speeds up to 30,000 r/min (Grease) while providing dependable radial load capacity. The MR137-ZZ serves as a core, reliable component in a broad range of small-scale mechanical and electromechanical assemblies.

Suited for a diverse range of precision equipment and compact mechanisms:
Small DC Motor Shafts
RC Model Vehicle Drivetrains
The miniature series design offers a robust yet space-saving solution with reliable radial load capacity for its size. Manufactured from high-carbon chrome steel, it ensures good durability and consistent performance in precision applications.
Features double metal shields (ZZ) as standard, providing effective protection against dust and particulate ingress while maintaining low rotational torque. This sealed-for-life design is ideal for applications where maintenance is impractical.
Manufactured to standard miniature bearing tolerances. The precision-ground raceways and balls ensure smooth, low-vibration, and quiet rotation, enabling efficient performance even at high rotational speeds.
| Bearing Type | Single Row Deep Groove Ball Bearing |
| ISO Dimension Series | MR Series – Miniature Series |
| Basic Designation | MR137 |
| Suffix | ZZ (Double Metal Shield) |
| Bore Diameter (d) | 7 mm |
| Outer Diameter (D) | 13 mm |
| Width (B) | 3 mm |
| Material (Races & Balls) | Chrome Steel (GCr15 / SAE 52100) |
| Precision Class | Standard / P5 Grade Available |
| Cage Material | Pressed Steel |
| Dynamic Load Rating (Cʳ) | 1.28 kN |
| Static Load Rating (C₀ʳ) | 0.48 kN |
| Limiting Speed (Grease) | 30,000 r/min |
| Limiting Speed (Oil) | 38,000 r/min |
| Weight (approx.) | 8 g |
Direct replacement for:
The MR137-ZZ comes as a ready-to-install, grease-lubricated bearing equipped with double metal contact shields (ZZ). This offers a robust, maintenance-free solution with fundamental protection against dust and dry debris. Alternative configurations, including different sealing options or open designs, are available upon request for specialized applications.
"For small precision drives, sensitive instruments, and compact mechanisms, the MR137-ZZ offers a dependable, shielded miniature bearing solution. Its standard ZZ shields help maintain consistent operation where preventing contamination ingress supports reliable long-term function."
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Details
The MR137-ZZ is a Miniature Double-Shielded Deep Groove Ball Bearing engineered for reliable performance in compact, precision applications. Utilizing the fundamental deep groove design, this small-diameter bearing is capable of supporting radial loads and very light axial loads in either direction. With a 7 mm bore and integrated double metal shields (ZZ) for basic contamination protection, it is an essential component for sensitive instruments, small motors, precision drives, and other applications where space is limited and smooth, low-friction operation is critical.
Details
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Details
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Details
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