Boya unidirectional microphone BY-VM01 is a compact and lightweight condenser microphone for video cameras or still cameras that can provide a better sound than built-in microphone of video DSLRs. The microphone can fix onto the camera hot shoe with its universal cold shoe adapter. For audio transmission, it is connected to the microphone jack of the camera via a 3.5mm mini-plug. Below the cold shoe connection is a thread, so the BY-VM01 can be attached externally onto a tripod. The microphone is equipment with a cable stop which holds the cable in place to prevent noise from being recorded with accidental. Type: Electret Condenser Sensitivity(+/-3dB ): -40dB +/- 3dB / 0dB=1V/Pa, 1kHz Frequency Response: 38-20,000Hz S/N ratio: 75dB or more Output Impedance: 1.0k Ω or less Power Source: 1.5V AAA battery Plug: Mini-pin plug (3.5mm) Weight: 62g Dimension(L*H*D): 109*75*18mm