The Sanken CUS-301 is a Cardioid Unidirectional Small Diaphragm Condensor manufactured and sold exclusively in the Japanese broadcast market in the 1970's and 1980's.
It is very difficult to find any information about this microphone but it's pretty safe to say that it is a rare mic, and being a Sanken, it's a damn fine mic.
It's a transformerless small diaphragm condenser and possesses the sonic traits you would expect from such a microphone - fast transient response and clear top end. What sets it apart from other SDC's is that it looks incredible. The large head basket/body is most likely designed to minimize the acoustic reflections of the body on the microphone's performance (much like the head basket on the Sony C500), as well as providing protection from plosives for vocal use.
This CUS-301 comes with it's original pouch, and has a brother with a very close serial number that is also available for purchase, in case you were interested in a pair.
