Unplug and enjoy. The MDR-RF4000K digital wireless headphones system gives you the freedom to travel up to 100 feet from your sound source while delivering phenomenal sound. This system includes Ni-MH rechargeable batteries, 2.4GHz RF digital transmission and headphones with a 40mm driver for deep bass. Includes charger and ultra-long battery life.
40mm drivers deliver deeper bass, lower distortion and wider dynamic range.
The supplied rechargeable NiMH battery lets you enjoy up to eight hours of continuous on a single charge1. The slim, folding design fits snugly into the charger (included). Substituting a single AAA battery for the rechargeable NiMH pack provides 10 hours of power.
Radio Frequency (RF) transmission sends signals from the transmitter to the headphones, allowing high fidelity sound reproduction. You can enjoy the accompanying reception range – up to 100 feet – even when you move outside the line of sight of the transmission.
A wide, self-adjusting headband distributes the headphone's weight over a wide area, reducing pressure and improving comfort.
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