Due to this high prevalence, vertebral artery hypoplasia (VAH) has not yet been considered an independent risk factor for ischemic stroke [1,2].
How to use your own headphones on Americanâs new 777-300ER. Passengers traveling in First and Business Class on Americanâs new 777-300ER are provided with Bose QuietComfort 15 Acoustic Noise Canceling headphones to use during the flight.
Definition of:headphones. Head-mounted speakers that position a pair of speakers over the ears. For listening to music or monitoring live performances, both left and right channels are required. When used with the telephone, a microphone is attached (see headset). Some of the Best Sound.