Sonic Balaclava Black â Large. Deflect cold air with warm, windproof WINDSTOPPER® Technical Fleece in the uniquely designed Sonic Balaclava. The vapor permeable WINDSTOPPER® Fleece offers maximum cold-weather protection, Polartec® Wind Pro® ear panels allow for better hearing, and a mesh breathing port means the only reason you'll be short of breath is the view.