Check the listing for details. Bose A20 Aviation Headset Electret Microphone Windscreen Mic Muff / Cover. Condition: New. Listed at 7.95 USD. Genuine Bose A20 Aviation Headset replacement Electret microphone windscreen. This replacement foam microphone screen reduces ambient noise and helps keep wind pressure from activating the microphone. Screen slides easily over headset microphone and is secured with integrated hooks on the microphone. This version does not need the rubber grommet. See my other auctions If you are looking for the version with the rubber grommet.Key featuresEffectively reduces wind and ambient puff noiseEasy to replace About Hobbs FlyerHobbs Flyer is a pilot-owned and operated aviation component manufacturer and retailer based in Minneapolis, Minnesota. We focus on bringing affordable, modern, and insanely comfortable aviation headsets and accessories to the aviation community. Visit our website to learn more.