A monitor arm is almost necessary for a truly ergonomic workstation, especially if it is a standing desk. Since the height between your eyes and the desk can vary and change, especially between sitting and standing, you need a monitor that will rise and lower to the ideal height.
The most significant internal difference between different models is whether they are built using air cylinders or compression springs.
The king of the Ergotron monitor arm line, the LX Sit-Stand has a wide range and capacity to give standing desk and treadmill desk users more options.
Single-display monitor arm with a mechanical spring function at a reasonable price to help improve ergonomic use of a standing desk.