MR126-ZZ Miniature Deep Groove Ball Bearing For Precision Mechanisms | 6×12×4 Mm
The MR126-ZZ is an Ultra-Compact Double-Shielded Deep Groove Ball Bearing engineered for reliable performance in space-constrained precision applications. Featuring the standard deep groove raceway design, this miniature bearing efficiently handles radial loads and minimal axial loads from both directions. With a 6 mm bore and built-in double metal shields (ZZ), it provides essential protection while maintaining low friction, making it an ideal component for small electric motors, sensitive instruments, micro-drives, and other compact devices where smooth, maintenance-free operation is critical.
MR126-ZZ Deep Groove Ball Bearing 6x12x4 mm | Micro Series | Double Metal Shields (ZZ)
This widely utilized micro-series bearing features the universal deep groove raceway design. Engineered for quiet and precise high-speed operation up to 45,000 r/min (Grease), it delivers reliable radial load support within an extremely minimal footprint. The MR126-ZZ is a fundamental component for applications where space is at an absolute premium.

Suited for ultra-compact precision equipment and micro-mechanisms:
Small DC Motor Spindles
RC Model Car and Drone Motors
The micro series design delivers reliable performance in an extremely small footprint with adequate radial load capacity for its size. Manufactured from high-carbon chrome steel, it ensures consistent operation and longevity in precision applications.
Features factory-installed double metal shields (ZZ) as standard, providing effective defense against dust and particulate ingress while maintaining very low rotational torque, ideal for maintenance-free, long-life designs.
Produced to standard miniature bearing tolerances. The precision-ground raceways and balls ensure exceptionally smooth, low-vibration, and quiet rotation, enabling stable performance at high rotational speeds.
| Bearing Type | Single Row Deep Groove Ball Bearing |
| ISO Dimension Series | MR Series – Micro Series |
| Basic Designation | MR126 |
| Suffix | Double Metal Shield (ZZ) |
| Bore Diameter (d) | 6 mm |
| Outer Diameter (D) | 12 mm |
| Width (B) | 4 mm |
| Material (Races & Balls) | Chrome Steel (GCr15 / SAE 52100) |
| Precision Class | Standard / P5 Grade Available |
| Cage Material | Stainless Steel or Pressed Steel |
| Dynamic Load Rating (Cʳ) | 0.95 kN |
| Static Load Rating (C₀ʳ) | 0.38 kN |
| Limiting Speed (Grease) | 45,000 r/min |
| Limiting Speed (Oil) | 56,000 r/min |
| Weight (approx.) | 3 g |
Direct replacement for:
The MR126-ZZ is supplied as a grease-lubricated, pre-shielded micro bearing featuring double metal contact shields (ZZ). This configuration provides a maintenance-free, sealed-for-life solution with effective protection against dry particulates. For applications with specific sealing needs or requiring an open design, alternative configurations can be requested.
"The MR126-ZZ is a key choice for sensitive micro-motors, instruments, and ultra-compact mechanisms. Its standard ZZ shields deliver reliable, consistent performance in environments where controlling fine contamination is essential for longevity."
The MR148-ZZ is a Robust Miniature Deep Groove Ball Bearing engineered for applications that require dependable performance with enhanced protection from contaminants. Featuring dual steel shields (ZZ) on both sides, this metric bearing provides a solid barrier against dust and airborne particles, helping to retain internal lubrication and promote smooth, extended service life. With an 8mm bore, it is well-suited for integration into small electromechanical systems, precision equipment, and motor assemblies where space efficiency and reliable sealing are key priorities.
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
The MR126-ZZ is an Ultra-Compact Double-Shielded Deep Groove Ball Bearing engineered for reliable performance in space-constrained precision applications. Featuring the standard deep groove raceway design, this miniature bearing efficiently handles radial loads and minimal axial loads from both directions. With a 6 mm bore and built-in double metal shields (ZZ), it provides essential protection while maintaining low friction, making it an ideal component for small electric motors, sensitive instruments, micro-drives, and other compact devices where smooth, maintenance-free operation is critical.
Details
The MR125-ZZ is a Double-Shielded Ultra-Miniature Deep Groove Ball Bearing engineered for precision and reliability in extremely space-limited applications. Utilizing the fundamental deep groove raceway, this micro-sized bearing is capable of supporting light radial loads and minimal axial loads from both directions. With a compact 5 mm bore and pre-installed double metal shields (ZZ) for protection, it is a critical component for sensitive instruments, micro-motors, optical devices, and other applications where minimal size, smooth operation, and contamination resistance are paramount.
Details
The MR117-2RS is an Ultra-Miniature Deep Groove Ball Bearing designed for applications where space is extremely limited and reliable sealing against contaminants is essential. Featuring double rubber contact seals (2RS) on both sides, this bearing provides superior protection against dust, moisture, and fine debris while maintaining smooth rotational performance. With a 7 mm bore and a compact 11×2.5 mm cross-section, it is ideal for micro motors, small instruments, precision mechanisms, and devices operating in challenging environmental conditions.
Details
The MR105 is a Miniature Deep Groove Ball Bearing designed for high-precision applications in compact assemblies where minimal friction and smooth operation are essential. With an open design (no seals or shields), this bearing offers unobstructed performance, making it ideal for clean environments, high-speed mechanisms, and applications requiring frequent re-lubrication. Featuring a 5 mm bore and compact 10×4 mm dimensions, it delivers reliable radial and axial load support in tight spaces.
Details
The MR128-2RS is a high-precision miniature ball bearing specifically developed for compact mechanical assemblies where internal clearances are tight and environmental protection is vital. Outfitted with dual contact rubber seals (2RS), this micro-bearing provides a superior barrier against fine dust and moisture while ensuring the internal lubricant remains stable during operation. With an 8mm bore, a 12mm outer diameter, and a slim 3.5mm width, it is the premier choice for RC racing components, small brushless motors, and precision dental tools requiring smooth, dependable rotation.
Details
The MR128-ZZ is a precision-engineered miniature ball bearing designed for high-velocity mechanical systems where low starting torque and minimal heat generation are essential. Featuring dual non-contact metal shields (ZZ), this micro-bearing provides reliable protection against larger debris while allowing the internal lubricant to operate at maximum efficiency. With an 8mm bore, a 12mm outer diameter, and a 3.5mm width, it serves as a critical high-performance component for cooling fans, high-frequency micro motors, and precision hobbyist electronics.
DetailsRequest a Quote for Ball Bearings
Scan to Wechat/Whatsapp :
