John Koss invented the first stereo headphone in 1958, and soon after, the Koss Corporation was born. Since then, they've created some of our favorite headphones, especially the Koss Porta Pro, which combine big sound and pocket-sized portability.
The NFC-enabled BT540i still offers classic, phenomenal sound—refined over 56 years—but adds that Bluetooth capability. This means what? It means that for the duration of the eight-hour charge, a headphone cable isn't knocking your water all over your keyboard. (Speaking from experience here.) And if you don't charge the battery, no big deal; Koss supplies you with a standard stereo miniplug cable so you can listen wired.