https://www.cnet.com/news/grados-first-bluetooth-headphone-signals-a-change-of-direction/ > The Grado feels cheaper than you might expect for the price, but the headband's padding feels slightly better than Grado's Prestige series 'phones. The GW100 is agreeably light on my head, and I found it more comfortable than most Grados. It's easy to wear for hours at a time. > Grado claims the GW100 is the world's first open-back Bluetooth (version 4.2 apt-X) design. The headphone's look is at once familiar, but cleaner and more modern, and a little less retro than other Grados.