• Micro Robotic Arm Joints & Actuators
• Gimbal Stabilization Motors
• Drone Brushless Motor Assemblies
• Compact Automated Guided Vehicle (AGV) Wheels

• 3D Printer Extruder Stepper Motors
• High-Speed Cooling Fan Rotors
• Precision Paper Feed Mechanisms
• Professional Plotter and Scanner Carriages

• Compact Handheld Rotary Tools
• Precision Spindles for Engraving
• Small Household Appliance Motors
• Miniature Gearbox Transmissions

• Dental and Surgical Handpieces
• Portable Diagnostic Centrifuges
• Precision Optical Rotary Stages
• High-Resolution Fluid Metering Pumps

01. Exceptional High-Speed Stability

Precision-machined to strict tolerance standards (Available in standard P0 up to P5 grades), the 684-ZZ utilizes high-grade steel balls and highly polished raceways. This advanced micro-engineering ensures negligible vibration and extremely low acoustic noise, allowing continuous, stable rotation at maximum operational velocities.

02. Twin Metallic Shields (ZZ) for Longevity

Fitted with two pressed steel shields, this bearing provides an excellent barrier against solid contaminants without inducing drag. Because the shields do not make physical contact with the inner ring, the bearing experiences zero frictional torque loss, translating to improved energy efficiency and prolonged equipment life.

03. Robust Micro-Scale Construction

Even with its highly compact 68 Series dimensions (4×9×4 mm), the 684-ZZ delivers a solid dynamic load rating of 0.64 kN. Forged from high-carbon GCr15 chromium steel, both the inner/outer rings and rolling elements provide exceptional surface hardness, effectively resisting fatigue and wear during continuous operation.

Interchange Part Numbers

Common manufacturer equivalents include:

• SKF: 684-2Z / W684-2Z
• NSK: 684ZZ
• NTN: 684ZZ
• KOYO: 684ZZ
• Timken: 684-ZZ

Design & Configuration

The 684-ZZ comes standard as a pre-lubricated, double-shielded unit, delivering immediate, plug-and-play reliability for high-speed, dust-sensitive environments. For specialized machinery necessitating absolute protection against moisture or liquid splashes, rubber-sealed variants (684-2RS) are available upon request. Conversely, for ultra-low torque or oil-bath configurations, unshielded open versions (684) can be supplied.

"Implement the 684-ZZ Shielded Miniature Bearing for compact mechanical designs where high-speed efficiency, minimal weight, and uncompromising durability are critical."