Xnrtop 4mm to 8mm Shaft Coupling 25mm Length 18mm Diameter Stepper Motor Coupler Aluminum Alloy Joint Connector for 3D Printer CNC Machine DIY Encoder(Pack of 2): Amazon.com: Industrial & Scientific
Nema17 stepper motor with 300mm lead screw 17HS4401 T8 Screw Lead 400mm 500mm 8mm 42 Motor 42BYGH With Screw for 3d Printer. - AliExpress Home Improvement