It looks, at first glance, like a fallen boundary marker or an abandoned building stone. Look more carefully at the northern edge of its upper face, however, and you can trace a run of ogham script stretching roughly a metre and a quarter from the eastern end. Ogham is an early medieval writing system, native to Ireland, in which letters are represented by notches and strokes cut along a central stemline, often the edge of a standing stone. The inscription here was read by the scholar R. A. S. Macalister in 1945 as CORBI KOI MAQI LABRID, a formula typical of early Irish commemorative stones, where MAQI means "son of", giving something close to "of Corb, here, son of Labraid".

Macalister recorded that the stone was originally upright, standing in the same field where it now lies recumbent. When or why it fell is not known. The slab itself tapers slightly from west to east, both in width and in thickness, a subtle shaping that suggests some degree of deliberate working rather than purely natural form. The stone measures 2.87 metres in length, with a maximum thickness of 0.45 metres. It carries National Monument designation, and has since been examined as part of the Ogham in 3D project run by the School of Celtic Studies at the Dublin Institute for Advanced Studies, which uses photogrammetry and three-dimensional modelling to document inscriptions that centuries of weathering have made difficult to read with the naked eye.

The stone sits beside the road in Ballyboodan, set within its own small enclosure at the edge of a field, which makes it relatively straightforward to locate and observe without disturbing the surrounding land. The inscription runs along the edge of the upper face, so getting a clear look requires positioning yourself to catch the light at a low angle, the kind of raking light that throws shallow cuts into relief. Early morning or late afternoon tends to work best for reading ogham on any stone of this kind.