Segments consist of volumetrically metered reactants (reaction mixture), which is capped on both the front and rear ends with immiscible solvent spacers (~50 µL on each end). Individual reactants within the segment may vary from 20 to 900 µLs.

Once the segment is constructed it is injected into a high pressure, temperature controlled flow system. A Transport Solvent such as Acetonitrile is used to transport the segment through the reactor. The flow rate of Transport Solvent and the reactor volume determines the segment's incubation rate.