R144ZZ Miniature Shielded Ball Bearing (3.175 x 6.35 x 2.779 mm)

Model: R144ZZ / R144-2Z

Product Highlights

Double Metal Shielded (ZZ) design to effectively keep lubricant in and dust/contaminants out
Ultra-precise 1/8" x 1/4" inch series sizing for compact mechanical assemblies
Low friction coefficient and minimal acoustic noise (< 20 dB) for smooth, high-speed operation
High-quality GCr15 Chrome Steel construction with high hardness, wear resistance, and fatigue strength
Pre-lubricated with premium industrial grease for immediate installation and long-term maintenance-free operation
Stamped steel cage ensures uniform ball spacing and stable rotation at high RPMs
100% dimensional and rotational accuracy test before shipment

Parameters	Specifications
Model / Bearing Designation	R144ZZ / R144-2Z
Bearing Type	Deep Groove Ball Bearing (Miniature Metric/Inch Series)
Bore Diameter (Inner Diameter)	3.175 mm / 0.125 in (1/8")
Outer Diameter (OD)	6.350 mm / 0.250 in (1/4")
Width / Thickness	2.779 mm / 0.1094 in
Closure Type	Double Metal Shielded (ZZ / 2Z)
Material (Rings & Balls)	Chrome Steel (GCr15 / AISI 52100) / Stainless Steel AISI 440C (Optional)
Cage Material	Stamping Steel / Stainless Steel
Precision Rating	ABEC-3 / ABEC-5 (P6 / P5)
Radial Internal Clearance	C0 (Standard) / C3
Limiting Speed (Grease)	Up to 48,000 RPM
Operating Temperature Range	-30°C to +120°C

Modern precision workshop, advanced CNC automated machining centers, and 100% full-inspection assembly lines.

Verified compliance with global standards, supporting smooth customs clearance and regulatory approvals across North America and Europe.