Condenser microphone with a high-frequency technology.
They are available in T12 or P48, plug or XLR 3-pin dyne, black or nikel.
they measure approximately 19mm in diameter by about 150mm long (XLR versions are a few millimeters of plus.Leur weight is around 140g depending on version.
I use it for some years. As most of the static, it is quite sensitive to wind. This is a very versatile mic to sound fairly neutral and accurate with very good dynamic for a static. I prefer it in quite a few cases some AKG Neumann among others and I am surprised that the MKH406 have not had more success in France.
His successor is the a priori MKH40 that still uses a different technology.