Befenybay 200mm 4080U Z-axis Screw Slide Table Linear Actuator Kit Linear Module for 3D Printer and DIY CNC Router Parts X Y Z Axis: Amazon.com: Industrial & Scientific
170mm Z Axis Slide Travel Cnc Router Linear Motion Kit For Reprap 3d Printer Cnc No/with Motor(second Hand Nema17stepper) - 3d Printer Parts & Accessories - AliExpress
Universal Z Axis Assembly - Feature Requests - Onefinity CNC Forum
Z Axis Assembly - 20mm Rails | 3D CAD Model Library | GrabCAD