Positive noise reduction rating: 24 dB

Active noise reduction rating: 23 dB(one of the most highest level in the world of the ANR)
Microphone Type: Amplified Noise Cancelling Electret Microphone
Microphone Frequency Response: 300 Hz --8k Hz
Speaker Type: Dynamic
Speaker Nominal Impedacnce: 300 ohm
Speaker Frequency Response: 150 ohm --20k
Plug: Microphone: 5.2 φ plug
Earhpone: 6.3 φ plug Stereo and mono opition
Earseals: Gel Earseals

Battery Box :9V