Voiced retroflex click

The voiced retroflex click is a rare click consonant. In practical orthography, an ad hoc symbol ⟨‼⟩ is used for the retroflex clicks; a voiced click with a velar rear articulation is ⟨ɡ͡‼⟩ or ⟨ɡ͜‼⟩, commonly abbreviated to ⟨ɡ‼⟩, ⟨ᶢ‼⟩ or ⟨‼̬⟩. The implicit symbol in the International Phonetic Alphabet is ⟨ɡ͡𝼊⟩ or ⟨ɡ͜𝼊⟩, abbreviated ⟨ɡ𝼊⟩, ⟨ᶢ𝼊⟩ or ⟨𝼊̬⟩. Linguists who prefer the old IPA letters use the analogous Doke convention of ⟨ɡ͡ψ⟩ or ⟨ɡ͜ψ⟩, abbreviated ⟨ɡψ⟩, ⟨ᶢψ⟩ or ⟨ψ̬⟩. For a click with a uvular rear articulation, the equivalents are ⟨ɢ͡‼, ɢ͜‼, ɢ‼, 𐞒‼⟩, ⟨ɢ͡𝼊, ɢ͜𝼊, ɢ𝼊, 𐞒𝼊⟩ and ⟨ɢ͡ψ, ɢ͜ψ, ɢψ, 𐞒ψ⟩. Sometimes the accompanying letter comes after the click letter, e.g. ⟨𝼊ɡ⟩ or ⟨𝼊ᶢ⟩; this may be a simple orthographic choice, or it may imply a difference in the relative timing of the releases.

Features
Features of the voiced retroflex click:

Occurrence
The voiced retroflex click is only confirmed from a single language, Central !Kung.