Used until 5 years ago. I haven't checked its operation recently. Please understand that this is a used item and has been stored at home. ---------- Below, I have copied the specifications of the same product from Rakuten Ichiba (Japanese online shopping site): Power Supply: Dry cell (AA) x 1 or Phantom DC9-52V Impedance: 250Ω Type: Back Electret Condenser Microphone Polar Pattern: Omnidirectional Frequency Response: 50～18,000Hz Sensitivity: -49dB±3dB (battery) -47dB±3dB (phantom) (0dB＝1V/Pa,1kHz) Battery Life: Approximately 1,000 hours Cable Length: 1.5m Output Terminal: XLR (power module) Dimensions: φ5 x 8.4mm (microphone unit), 76 x 64 x 29mm (power module) Weight: 14g (microphone unit), 150g (power module, excluding battery)