I see you posted the same question on gearslutz

As far
as I can see there is no Mk IV. If it has a presence boost adapter, a red warning light
for low battery and is silver in colour and a noise level of 21 dB(A) then it is the same
as the MkIII most likely.
The part number for the current model is AKG0075, what part
number does the MkIV have?
P.S. I looked on the harman-akg website as well!
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