Under-Mount Sink Installation Under-Mount sink can be installed with two different reveals Reveal, Flush Deciding on your preferred Look must be done prior to installation. (See diagram) Reveal The counter top edge sits approximately 1/4™ back 2 7 from the edge of the sink, exposing the sink rim. Flush The counter top meets the edge of the sink, fitting 7 7 flush with the sink bowls. For solid surface counter top installations only ie: granite, quartz, stone etc.