Mechanical guide supporting Z-axis movement.

Difference between reference and actual Z-axis positions.

Structural assembly supporting Z-axis movement.

Small gear engaging a rack.

Bearing supporting movement along a Z-axis.

Total distance available along the Z-axis.

Precision guide for Z-axis travel.

Mechanism holding a Z-axis assembly stationary.

Actuator producing controlled Z-axis movement.

Smallest measurable or controllable Z-axis movement.