Visor
"The Dyson Zone headphones come with a removable "visor" that uses a pair of compressors and electrostatic filters to "project purified air at the wearer's nose and mouth.""
A visor, by definition, goes in front of your eyes. The similarity to the word "vision" is not coincidental. On the other hand, using this thing as a visor would probably look just as sensible and provide precisely the same level of protection.
Biting the hand that feeds IT
