QZ900
Koss QZ900 noise cancelling headphones will create less reason to turn up volume and overdrive the tiny amplifier in your portable electronics. This means greater efficiency, less distortion, deep rich lows, and sparkling highs.
Unlike most other noise cancelling headphones, QZ900s play music with or without the active noise cancelling circuit engaged. A handy removable cord features an in-line volume control, and one standard AAA battery provides approximately 50 hours of active noise cancellation.
Features: