This wireless headphone system consists of a pair of wireless headphones (HDR 160) and a compact transmitter (TX 160) which runs on AC or battery power to best accommodate your application. The transmitter's compact size makes it a natural selection for automotive installs or in dentist/doctor's offices. The RS 160 utilizes KLEER's lossless digital wireless audio transmission (it sounds wired!), offering a range of up to 60 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. The headphones' leatherette earpads and headband cushions provide outstanding comfort while their closed, around-the-ear design prevents sound leakage.