This is the second version of the PlainTalk Microphone produced by Apple. The first version was round. This model has a unique curvy shape with a flat bottom with a lip to allow it to sit flat on top of a computer display. This microphone was compatible with desktop Power Mac models up to and including G3 iMac models. It measures 50 x 25 x 60 mm.
The microphone is powered by an internal amplifier that receives its power from its elongated tip of its 3.5 mm jack plug. The extra-long tip makes this connection proprietary.
The microphone is omnidirectional, but records only in mono.
Source: Radio Museum