The RS 170 wireless headphone system is made up of a pair of wireless headphones (HDR 170) and a multi-purpose transmitter (TX 170) which also functions as an 'easy-charge' cradle and docking station. The RS 170 also features a dynamic bass boost and surround sound simulation mode for edge-of-your-seat excitement with your favorite music and movies. The RS 170 utilizes KLEER's lossless digital wireless audio transmission (it sounds wired!), offering a range of up to 260 feet, audiophile-grade sound and reception to four optional pairs of Sennheiser KLEER headphones. Never fuss with tuning again thanks to automatic, interference-free pairing between the headphone and transmitter. An exceptionally detailed, full-bodied sound reproduction is pumped into the listeners ears, filling the sealed, private earcups with liquid smooth audio. The headphones' leatherette earpads and headband cushions deliver outstanding comfort while their closed, around-the-ear design prevents sound leakage.