Cyber Acoustics ACM-800 Noise Cancelling Headphones (Discontinued by Manufacturer) Noise canceling with foldable headband Gold plated 3.5mm stereo plug Sensitivity: 113dB +- 3dB(OFF) / 119dB +-3dB(ON) Frequency Response: 20-20KHz Reduction level: &gt;= 12dB at 300 Hz