Shure 300 Bi-Directional Gradient

The 300 Studio gradient is a bi-directional microphone for
broasdcasting,recording and sound reinforcement which
provides sound pickup at front and rear, but greatly
reduces pick-up at the sides. This microphone can be
placed at a greater distance than an omnidirectional one.

Bertie Chancellor of Tennsville fame ( Radio Demerara)