4mm Bore Bearing - 12mm Pulley U-Groove Track Roller 4x12x4mm

4mm Bore Shielded U-Groove Pulley Bearing
✔️ Track Roller Ball Bearing - 4mm x 12mm x 4mm

This compact U-groove track roller bearing features a 4mm bore and double metal shields to protect against dust. Ideal for small tracks, sliding systems, and lightweight guiding applications in automation or DIY builds.

✅ Size: 4mm x 12mm x 4mm
✅ Inner diameter: 4mm
✅ Outer diameter: 12mm
✅ Tire width: 4mm
✅ Groove type: U-groove
✅ Shields: Double metal (ZZ)
✅ Quantity: 1 bearing
✅ Tolerance: ±0.5mm

💡 Why use a shielded U-groove pulley bearing in track systems?
It’s perfect for reducing friction while guiding movement on round or angled rails.
Used in 3D printers, robotics, and sliding gates
✅ Metal shields block debris and extend bearing life
✅ U-groove profile keeps rolling motion aligned on tracks
✅ Compact size fits tight motion systems

Tiny but tough - this bearing is built for clean tracking and smooth gliding. Grab one now and roll with precision!