Upgrade your Bose A20 or A30 Aviation Headset with a fresh windscreen to maintain optimal performance. Over time, mic muffs can collect dirt and dust, affecting voice clarity and noise cancellation. By replacing your windscreen with this OEM original from Bose, you ensure top-notch noise-canceling capability. Each windscreen comes with an O-ring included. Keep extras handy in your flight bag for quick changes between passengers.