The remains at Kilnatoora, south of the Tourig river in east Cork, began their life as a fulling mill, and the millstone sitting nearby, measuring 1.32 metres in diameter, suggests that at some point the operation shifted toward grinding grain instead. Fulling mills, sometimes called tuck mills, were used to clean and thicken woven cloth by pounding it in water, a process that required significant mechanical force transferred from a waterwheel. The name recorded on the 1842 Ordnance Survey six-inch map is Tuck Mill, which is simply an older term for the same process, tucking being the traditional English word for fulling.

The structure itself is rectangular, measuring roughly 8.4 metres east to west and approximately 6.2 metres north to south on the interior, though the southern end no longer survives. What does remain is substantially overgrown, but a stone arch in the eastern wall is still legible enough to read: it marks the point where power was transferred from the wheel-pit beside the building into the machinery within. Wheel-pits of this kind housed the waterwheel itself, channelling water beneath or against the wheel to drive the mechanism inside. The presence of the large millstone nearby, rather than incorporated into the structure, is what complicates the picture, since fulling mills did not use millstones at all. It may point to a later phase of use, or perhaps a conversion that was never fully completed.