Leave A Message
If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.
Submit
R Series
Home Deep Groove Ball Bearings R Series

R166-ZZ Double Shielded Miniature Ball Bearing | Dust-Proof Precision | 4.762 × 9.525 × 3.175 mm

R166-ZZ Double Shielded Miniature Ball Bearing | Dust-Proof Precision | 4.762 × 9.525 × 3.175 mm

The R166-ZZ is a highly versatile inch-series miniature ball bearing designed for environments where both reliable rotation and protection from airborne debris are critical. By utilizing a double-shielded ("ZZ") configuration, this bearing effectively locks in factory-applied grease while blocking dust, dirt, and fine particulate matter from entering the raceways. With its standard 3/16-inch bore, the R166-ZZ is an essential, maintenance-free component for compact electric motors, hobbyist models, and precision commercial equipment requiring sustained, smooth performance without regular relubrication.

R166-ZZ Deep Groove Ball Bearing 4.762 × 9.525 × 3.175 mm | R Series – Extended Lifespan & Contaminant Resistance

Engineered for longevity and stable mechanics, the enclosed architecture of the R166-ZZ makes it highly resistant to harsh operating conditions. The non-contact metal shields sit flush within the outer ring, maintaining an optimal balance: they provide excellent barrier protection without adding the heavy rotational drag associated with rubber seals. Whether installed in automated office equipment or a heavy-duty RC vehicle, this bearing delivers quiet, efficient power transmission and reduces equipment downtime by protecting the internal rolling elements from premature wear.

R166-ZZ Double Shielded Miniature Ball Bearing | Dust-Proof Precision | 4.762 × 9.525 × 3.175 mm

Comprehensive Applications

Highly recommended for mechanical engineers and technicians looking for dependable, shielded performance in 3/16-inch shaft applications:

Hobby & RC Equipment
  • Radio-Controlled (RC) Cars and Helicopters
  • Slot Car Motor Assemblies
  • Model Train Drivetrains
  • Drone Gimbal Mechanisms
Office & Automation Machinery
  • High-Volume Commercial Printers
  • Automated Sorting Spindles
  • Currency Counting Machines
  • Precision Stepper Motors
Medical & Scientific Devices
  • Handheld Dental Tools
  • Diagnostic Centrifuges
  • Automated Fluid Pumps
  • Laboratory Dial Indicators

Key Performance Features

01. Dual Metal Shielding (ZZ)

A core advantage of the R166-ZZ is its twin pressed-steel shields. These enclosures securely retain the internal lubricant while deflecting external debris. Because the shields do not make physical contact with the inner ring, the bearing still achieves exceptional high-speed capabilities while remaining fully maintenance-free throughout its operational life.

02. Standardized Imperial Footprint

Measuring exactly 4.762 mm (3/16") at the bore and 9.525 mm (3/8") across the outer diameter, this bearing provides drop-in compatibility for standard inch-based mechanical assemblies. Its narrow 3.175 mm (1/8") width allows for efficient stacking or placement in severely space-restricted housings.

03. High-Carbon GCr15 Chrome Steel

Manufactured from strictly graded GCr15 Chrome Steel (SAE 52100), the inner and outer rings, as well as the ball elements, deliver P5-grade dimensional accuracy. This extensive heat-treatment process guarantees excellent load-bearing capacity, high surface hardness, and superior resistance against metal fatigue during continuous cycling.

Technical Specifications

Bearing Type Single Row Deep Groove Ball Bearing
ISO Dimension Series R Series (Miniature Imperial / Inch)
Basic Designation R166
Suffix Options ZZ (Dual Metal Shields)
Bore Diameter (d) 4.762 mm (3/16")
Outer Diameter (D) 9.525 mm (3/8")
Width (B) 3.175 mm (1/8")
Material (Races & Balls) Chrome Steel (GCr15 / SAE 52100) or Stainless Steel (AISI 440C)
Precision Class Standard / P5 Grade Available
Cage Material Pressed Steel (ribbon type) or Polyamide
Dynamic Load Rating (Cʳ) 0.713 kN (713 N)
Static Load Rating (C₀ʳ) 0.273 kN (273 N)
Limiting Speed (Grease) 40,000 r/min
Limiting Speed (Oil) -
Weight (approx.) 0.0008 kg (0.8 grams)

Interchange Part Numbers

Cross-reference equivalents to streamline your purchasing process:

  • NMB: R-1030ZZ
  • SKF: R166-2Z
  • FAG: R166-2Z
  • NSK: R166ZZ
  • NTN: R166ZZ
  • Barden: R166SS
  • KOYO: R166ZZ

Design & Configuration

For over 15 years, Welink Bearing has delivered precise rotational solutions to global manufacturing sectors. The R166-ZZ represents our commitment to durability in compact forms. All our double-shielded miniature bearings arrive factory-lubricated with premium lithium-based grease, fully ready for immediate installation. We also provide customized lubricant fills (from wide-temperature greases to low-noise synthetic variants) to perfectly match your specific motor or application requirements.

"Secure your micro-mechanisms with the R166-ZZ bearing—delivering shielded durability, standard inch precision, and maintenance-free reliability for demanding applications.”

Download Product Catalog (PDF)

Related Products

R155-ZZ Miniature Bearing showing Double Metal Shields for Factory Grease Retention and Debris Protection in Small Motors
R155-ZZ Shielded Miniature Ball Bearing | 5/32" Bore Precision | 3.967 × 7.938 × 3.175 mm

The R155-ZZ is a precision-engineered imperial miniature ball bearing specifically developed for applications requiring a 5/32-inch shaft interface. Featuring a dual-shielded ("ZZ") construction, this model provides a robust defense against dust and debris, ensuring the internal raceways remain clean and well-lubricated. This enclosed design makes the R155-ZZ an ideal, "set-and-forget" component for high-speed micro-motors, precision encoders, and small-scale mechanical linkages where reliability and low-maintenance operation are paramount.

Details
R155-2RS Miniature Ball Bearing with Dual Rubber Seals for Dust and Moisture Protection in Medical Robotics
R155-2RS Sealed Deep Groove Ball Bearing | Precision Shielded Micro Rotation | 3.967 × 7.938 × 3.175 mm

The R155-2RS is a high-performance miniature imperial ball bearing engineered for specialized applications requiring a contaminant-free environment within a compact footprint. Featuring dual-sided Nitrile Rubber (2RS) contact seals, this bearing provides an exceptional barrier against dust, moisture, and fine particulates while ensuring excellent grease retention. Designed for 5/32-inch shafts, the R155-2RS is a vital component for high-precision instruments and micro-mechanisms where long-term reliability and zero maintenance are paramount.

Details
R2A-ZZ Miniature Ball Bearing showing Dual Steel Shields for Maintenance-Free Performance and Dust Protection
R2A-ZZ Shielded Miniature Ball Bearing | Heavy-Duty Micro Rotation | 3.175 × 12.7 × 4.366 mm

The R2A-ZZ is a specialized imperial miniature ball bearing designed for applications that require a small 1/8-inch bore but demand higher load-bearing stability than standard micro-bearings. Featuring an exceptionally robust 1/2-inch outer diameter relative to its bore size, the R2A-ZZ offers enhanced structural rigidity and radial strength. The double-shielded ("ZZ") configuration utilizes two non-contact metal plates to retain high-performance lubricant while acting as a barrier against dust and environmental contaminants, making it a reliable choice for high-speed, maintenance-free operation.

Details
Precision R2-6-ZZ 1/8 Inch Bore Bearing in GCr15 Chrome Steel compatible with SKF R2-6-2Z and NSK R2-6ZZ for Micro Motors
R2-6-ZZ Shielded Deep Groove Ball Bearing | High-Stability Miniature Rotation | 3.175 × 9.525 × 3.967 mm

The R2-6-ZZ is a high-performance miniature imperial ball bearing engineered for applications that require a balance of compact sizing and enhanced structural rigidity. Featuring dual metal shields (ZZ), this bearing is designed to retain high-speed lubricant while providing a robust physical barrier against larger contaminants and debris. With its 1/8-inch bore and a wider-profile 5/32-inch width, the R2-6-ZZ offers superior radial load support compared to ultra-slim variants, making it ideal for precision motors and mechanical drive systems.

Details
Precision 1/8 Inch Bore R2-6-2RS Replacement Bearing compatible with SKF R2-6-2RS and NSK R2-6-2RS for Power Tools
R2-6-2RS Sealed Miniature Ball Bearing | Moisture & Dust Protection | 3.175 × 9.525 × 3.967 mm

The R2-6-2RS is a high-performance imperial miniature bearing specifically engineered for environments where exposure to moisture, dust, or fine particulates is a concern. Featuring a dual-contact rubber seal ("2RS") design, this bearing provides a superior airtight enclosure compared to metal shields. The synthetic rubber seals are reinforced with steel inserts, ensuring that the factory-applied grease remains securely inside the raceways while effectively blocking external contaminants. With a standard 1/8-inch bore and a 3/8-inch outer diameter, the R2-6-2RS is the ideal choice for outdoor equipment, small power tools, and high-precision mechanical assemblies operating in demanding conditions.

Details
High Speed 50000 RPM R2-5 ZZ Bearing - GCr15 Chrome Steel Construction with P5 Precision for Robotics and Micro-Spindles
R2-5-ZZ Inch Series Miniature Ball Bearing | High-Performance Precision | 3.175×7.938×3.571mm

The R2-5-ZZ is a precision-engineered, inch-series miniature deep groove ball bearing designed for applications where rotational stability and radial clearance control are paramount. With a 1/8" bore diameter, this model is slightly more robust than the ultra-micro series, offering a balanced power-to-size ratio. It is equipped with dual metallic shields (ZZ) that provide a physical barrier against workplace debris while maintaining a non-contact interface with the inner ring to prevent friction-induced heat. This specialized construction ensures the R2-5-ZZ remains the preferred choice for high-speed micro-motors and sensitive transmission systems.

Details
Precision R2-5-2RS Miniature Ball Bearing showing Double Contact Rubber Seals for Moisture Protection in RC Vehicles and Micro-Motors
R2-5-2RS Inch Series Miniature Ball Bearing | Sealed Contamination Defense | 3.175×7.938×3.571mm

The R2-5-2RS is a highly resilient inch-series miniature deep groove ball bearing engineered to deliver reliable rotation in environments prone to dust and moisture. Featuring a standard 1/8" inner diameter, this micro bearing is equipped with dual contact rubber seals (2RS) crafted from durable NBR (Nitrile Butadiene Rubber). Unlike standard metal shields, these contact seals create a physical barrier against external particle ingress and fluid splashes. This heavily shielded architecture effectively locks in premium factory grease while preventing abrasive contaminants from reaching the raceways, making the R2-5-2RS an essential component for demanding outdoor applications and exposed micro-mechanisms.

Details
Precision R2-5 Open replacement bearing matching SKF R2-5 and NMB RI-518 for enclosed stepper motors and precision gearboxes
R2-5 Open Inch Series Miniature Ball Bearing | Ultra-Low Friction & High-Speed Dynamics | 3.175×7.938×2.779mm

The R2-5 Open is a precision-engineered, inch-dimensional miniature deep groove ball bearing developed specifically for applications demanding absolute minimum rotational resistance. With a standard 1/8" bore diameter, this bearing utilizes an entirely unshielded (open) architecture. By eliminating the physical barriers of shields or rubber seals, the R2-5 Open achieves a zero-contact environment that eradicates frictional drag. This design is highly favored for mechanisms housed within clean, enclosed environments or oil-bath systems, where maximum RPM and rapid heat dissipation are critical for system performance.

Details

Leave A Message

Leave A Message
If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.
Submit

Home

Products

whatsApp

contact