Appearance
The shell is of moderate size, very solid, globose-oval, and smooth except for weak shallowly incised spiral lines. The external shell colour is black, but the aperture is white, except for a narrow black border. Once shells get over about 26mm they start to wear down and typically have knotched sides and a white wear on the right hand side of the shell.
The operculum is granular, pinkish-lilac, with two spiral bands of black.
The shell height is up to 30 mm, and width 32 mm.

