The Sony MDR-RF855RK is a pair of wireless over-ear headphones designed for comfortable home listening. They utilize radio frequency technology to provide a generous range of up to 100 meters, allowing you to move freely around your living space without being tethered to your audio source. The sound is driven by 40 mm neodymium dome drivers that cover a wide frequency range from 10 Hz to 22,000 Hz, while the closed-back design helps isolate you from ambient noise. To make daily use easier, these headphones feature an auto power on/off function that activates as soon as you put them on. If you are watching a movie or a news program, the dedicated voice mode enhances dialogue clarity so you can hear speech more distinctly. You can easily adjust the volume using the rotary controls located directly on the earcups. Power is provided by a rechargeable Ni-MH battery that offers about 18 hours of use on a single charge, which takes roughly 7 hours to complete. When you are finished, simply place the headphones on the included transmitter cradle to recharge them. The system comes with a TMR-RF855R stereo RF transmitter that connects via analog pin or stereo mini-jack inputs, making it a practical choice for those who want wireless freedom without relying on Bluetooth pairing.