Ogham, the early medieval Irish script that encodes names and lineages as a series of notches and strokes along a central line, was carved on standing stones, and those stones were meant to be seen. Yet when this particular example was found by a researcher named Hitchcock, it was lying flat in the inner chamber of a souterrain, a type of underground stone-lined passage associated with early Irish settlements, serving as one of the roofing slabs of the tunnel. It had been repurposed, probably centuries before anyone thought to look for it, by people who needed building material more than they needed an ancestor's name preserved upright in the ground.

The stone measures 1.83 metres and carries an inscription in the Primitive Irish formulaic style typical of early ogham monuments: a personal name, a patronymic introduced by MAQI (meaning "son of"), and a tribal or kin group introduced by MUCOI. The inscription reads, in Macalister's 1945 transcription, as CATTUVVIRR MAQI RITUVVECAS MUCOI ALLATO, though O'Kelly, writing in 1954, read the second name slightly differently as RITTAVVECAS. The variation is minor but it illustrates how much interpretation goes into deciphering deeply worn or ambiguously notched letters. The souterrain in which the stone was found formed part of a large rath, a circular earthen enclosure used as a farmstead in the early medieval period, and the ruined church of Kilgarrylanders lies close by to the north-west, suggesting this corner of Kerry was a well-settled and significant place. Macalister catalogued the stone under the name "Corkaboy", the townland in which it originally stood, though boundary changes have since placed the site within the townland of Keel. After its discovery, the stone was moved to a position in front of what was then a police barracks and is now a farmhouse.