You are looking at an unused core sound ambisonics tetramic included with all the connectors you may need.

Comes bundled with cables and shock mount

Core Sound is pleased to offer its groundbreaking TetraMic, the first portable, single point, stereo & surround sound Ambisonic soundfield microphone for most multi-track recorders and audio interfaces. Individually calibrated, each TetraMic is the finest performing microphone of its type in the world. Compare its performance to similar soundfield microphones you'll be quite amazed.

Based on the principles of Ambisonic recording developed by Michael Gerzon and Peter Craven during the 1970's, TetraMic allows you to place a single exceedingly accurate tetrahedral microphone in a sound field, record four channels of audio in "A" format, transform them using software into "B" format (W, X, Y and Z), and later interpret those four channels to essentially any single-point configuration of microphones