12 Pack Small U Groove Pulley Bearings 4x13x4mm For Rail Track Linear Motion Systems, Miniature Aluminum Alloy Pulleys, Replacement Roller Wheel Set For Easy Install And Smooth Operation

12-Pack Mini U-Groove Pulleys 4x13x4mm for Smooth Motion
✔️ Width 4 mm (0.16 in), Ø13 mm (0.51 in), ID 4 mm (0.16 in), 12 pcs

These compact aluminum alloy U-groove pulleys ride on standard rails, providing precise, low-friction guidance in linear motion systems. They're perfect for DIY projects, 3D printers, sliding doors, drawers, and small automation builds.

✅ Wheel diameter Ø13 mm (0.51 in), bore Ø4 mm (0.16 in)
✅ Width 4 mm (0.16 in), groove width 2.2 mm (0.09 in)
✅ Material: aluminum alloy, durable for long service life
✅ Sealed design keeps lubricant in for low-maintenance operation
✅ Package: 12 pulleys per pack for easy replacement

💡 What is a small U-groove pulley bearing used for in compact linear motion systems? This handy part guides components along rails with minimal friction. - Handy for DIY projects like 3D printers, sliding doors, and drawers - Improves tracking on rails with a deep V groove for stable motion - Easy to install and replace in tight spaces with standard rail sizes