The fully assembled MAS 2.0 system is shown in Figure . In addition to the components already described, additional covers provide protection against dust, optical distortions due to the air movement, and damage to sensitive components. In addition to the covers shown in this picture, the entire optical system and breadboard is covered with an enclosure made up from aluminum rails and acrylic panels (not shown), such that easy access to the flow cell area is provided by a sliding panel. The chemical delivery system, an Expedite 8909 nucleic acid synthesizer, can be seen under the optical workstation. This is placed directly below the flow cell in order to minimize length of the connecting tubing (not shown).