It is a baptismal font, solid and ancient-looking, measuring roughly 68 centimetres across and 56 centimetres high, with a basin hollowed into its top and a small drain hole that channels water out through the side of the stone via a cut groove. What gives it a slightly unsettled quality is knowing it did not originate here at all, but was moved to the church from somewhere else entirely, some point before 1933.

The font's original home was Ballymaghroe Graveyard, a short distance away in the Wicklow uplands. Exactly when it was relocated, or precisely why, is not recorded, but the transfer was already accomplished by the time Corlett and Weaver documented it in their 2002 study of the area's early monuments. The stone itself is a substantial piece of work. Around its outer surface, two crosses face one another on opposite sides, both carved in low relief using a raised band technique, where the form of the cross is built up slightly proud of the surrounding stone rather than cut into it. One cross survives largely intact, standing nearly half a metre tall. The second has lost its upper arm to damage at the top of the font, leaving only the lower portion visible. The same damage that truncated the cross has also broken the upper edge of the basin itself, so the stone carries its history of rough handling quite visibly.

The church at Knockananna is no longer in regular use, and the font sits within it in a kind of quiet limbo, a piece of early ecclesiastical stonework displaced from its graveyard context and held, for the time being, somewhere safer. Whether the basin was ever used for baptism at Ballymaghroe or served some other ritual function there is not known. What remains is the granite itself, patient and heavy, with its two carved crosses and its careful little drain.