This species is really variable as far as colour and number of spiral cords are concerned. It is undoubtedly conic in shell with whorls wide and flat-sided. Only last whorls of very large specimens are a little bit convex, protoconch sharp. Upper whorls have three spiral belts. In the following whorls, between the first and the third one, it forms one thin belt which will be the fourth little cord present on the rest of whorls. In very large specimens it is possible to reckon either one or two additional little cords on last whorls. On last whorl there are always present some varices, but they can be present on previous whorls too. Brown reddish in colour with spiral cords darker in colour. Varices are always dirty white in colour. It is recognizable from its similar one B. reticulatum since it has three cords only on first whorls and the additional fourth one (between the first and third one) on the following whorls only, while reticulatum has the first two adapical cords really close among them, moreover as far as reticulatum is concerned, varices are present all over spiral length. Average measures of adult specimens are around 10-12 mm in height.

Habitat: it lives on algal bottoms in the infralittoral zone. Distribution: quite common all over the Mediterranean.