Features – uses ms (mid-side) stereo sound pickup system, pickup the natural sound, transmit ultra clear stereo sound quality. Can be set up according to the sound source and individual be fond of pickup pattern (impact range width) to 900 or 1200. Specification – type – ms (mid-side) stereo wire, length – about 28cm, power requirement – 3v cr2 battery, battery life – about 800 hours, size – 30. 5X61x132. 5Mm, performance parameters – frequency response – 30-15000hz, sensitivity – -40db±2db(0db=1v/pa1khz), pointing to the features – single directional x 2, output impedance – 200?, single-to-noise ratio – 76db (1 kHz at 1pa), the loudest level – 120db at 1 kHz harmonic distortion 1 percent or less, power supply – 3v dc.