Rotatable Universal Shaft U Joint Coupler for Motors, 3D Printers and CNC Machines, 5 Pack, Fits 3mm to 5mm Inner, M4 Thread, 23mm Long, 11mm OD, Silver Tone, DIY Robot Linkage Connector

Rotatable Universal Shaft U Joint Coupler for Motors
✔️ 5-pack, M4 thread; bore 3-5 mm; 23 mm long, 11 mm OD

These rotatable universal shaft U joint couplers are nickel-coated iron links designed to connect motor shafts to hex wheels in robotics and DIY projects. They’re commonly used in RC cars, 3D printers, and CNC machines to transmit torque while keeping shafts aligned.

✅ Thread Size: M4
✅ Inner Diameter: 3-5 mm (0.12-0.20 inch)
✅ Length: 23 mm (0.91 inch)
✅ Outer Diameter: 11 mm (0.43 inch)
✅ Material: Nickel-coated iron

💡 What is a universal joint coupling used for in hobby robotics and DIY projects? A handy connector that transfers torque while keeping shafts aligned.

- Transfers torque between shafts at small angles
- Improves alignment in RC cars, printers, and CNC rigs
- Easy to install with standard M4 hardware