Voiced bilabial flap

A voiced bilabial flap is an uncommon non-rhotic flap. It is usually, and perhaps always, an allophone of the labiodental flap, though it is the preferred allophone in a minority of languages such as Banda and some of its neighbors.
In Mono, the sound has been described as follows:
And, for allophony between the bilabial and labiodental flap,
In the literature, this sound has most often been transcribed with, a modified by an extra-short diacritic. A less frequently used alternative transcription is, a labiodental flap modified by an
advanced diacritic. In addition, the symbol, a W with hook, is supported by SIL Global as a para-IPA transcription for this sound.