Voussoirs are the wedge-shaped stones that form the curve of an arch, each one cut to lock against its neighbours under pressure rather than mortar. When they survive scattered and out of position, as these do, they speak quietly to an arch that no longer exists, a doorway or chancel opening that has long since fallen or been dismantled, leaving only its constituent pieces behind.

St Finan's church sits on an island associated with early Christian monasticism in south-west Kerry, a region dense with such remains, from beehive cells to inscribed grave slabs. The four voussoirs recorded here are catalogued among the architectural fragments of the site, documented by O'Sullivan and Sheehan in their 1996 survey of south-west Kerry. That they remain in the chancel rather than having been removed or lost entirely is itself notable; architectural fragments from small island churches have frequently been displaced over centuries of casual disturbance, salvage, or simple neglect.