easy z axis linear motion

this is my Z axis linear motion relly easy and chep by RoboGio

part list:
- x2 8mm linear rod
- x1 NEMA 17
-x2 8mm internal bearing (22 out diameter)
-x1 8mm x 1.25 (comun use) threded rod
-x2 8mm linear bushings
-x1 8mm nut