Pack of 4 SBR12UU bimetalseal, micro deep groove carriage block bearings designed for linear support rails and CNC applications. These bearings deliver reliable, lowfriction linear motion and protect moving parts from contamination to extend service life. Key benefits Reliable linear motion: deep groove ball design minimizes friction for smooth carriage travel and stable positioning. Protection against contaminants: bimetal seal shields reduce ingress of dust and debris, helping bearings last longer in workshop environments. Easy replacement and upgrade: direct dropin fit for standard SBR12UU carriage blocks and 12 mm linear shafts, making maintenance and retrofits fast and simple. Economical pack: four matching bearings allow replacement of a full carriage or multiple mounting points in one . Key attributes Model: SBR12UU (pack of 4) Functionality: micro deep groove ball bearings configured as carriage block support bearings for linear rails Seal type: bimetal seal shield for improved contamination resistance Compatibility: intended for standard 12 mm linear shafts and SBR12 series linear rail/carriage applications Performance: smooth, lownoise operation suitable for precision hobbyist and light industrial uses How this solves common problems Reduces play and vibration that cause poor cut quality or print artifacts by providing consistent, lowfriction guidance. Limits downtime: the bimetal seal helps prevent premature wear from dust and chips, reducing the need for frequent replacements. Simplifies maintenance: standard sizing and form factor allow quick swapouts without machining or modification. Typical use cases CNC routers and milling machines: worn carriage block bearings to restore smooth axis travel and improve surface finish. 3D printers and CNC convert kits: upgrade or linear motion axes using standard 12 mm shafts and SBR12UU blocks. Light automation and robotics: provide dependable linear support for sliders, pickandplace stages, and small gantries. Installation and compatibility notes Designed as a direct replacement for SBR12UU carriage block bearings; confirm shaft diameter (12 mm) and block size before installation. Pack contains four identical SBR12UU bearings to service one carriage or multiple mounting points. This pack of 4 SBR12UU bimetalseal micro deep groove bearings is a practical choice when you need dependable, protected linear support for CNC, 3D printing, and light automation projects.