Hella Durable Open Type Linear Ball Bearings With Nickel Plated Steel Shell Kickass Linear Motion Bushings For Snappy Sliding Action Pack Of Four Pieces Shaft 12 mm Outer 21 mm Length 30 mm Perfect For Cnc And Diy Projects

Set of Four 12mm Linear Ball Bearings For CNC And DIY Guides
✔️ Shaft 12mm (0.472in). Outer 21mm. Length 30mm. Steel core unit

You receive four open style roller sleeves per package. These low friction bushings glide over round metal rods. You will install them on custom laser gravers or diy test rigs. The nickel plated coating blocks shop dust and prevents rust during long runs.

✅ Open design mounts directly onto standard guide plates
✅ Inner shaft measures 12mm (0.472in) for precise rod fit
✅ Outer cylinder spans 21mm (0.827in) for solid rail spacing
✅ Total body runs 30mm (1.18in) for stable alignment
✅ Hardened steel core handles repeated back and forward motion
✅ Smooth sliding action reduces motor strain on your drive axis

💡 What makes a linear slide bearing handy for moving heavy tool heads?
Choosing the right rolling element assembly improves machine accuracy and cuts wear on moving rails.
- The reinforced inner race maintains roundness under cutting loads
- Standardized measurements make swapping older parts super easy
- Direct metal contact delivers consistent tracking without extra play