Wireless Headphone System...The HA-W600RF lets you enjoy great sound anywhere in your home. This wireless 900MHz headphone with a 164 foot range (approximate) can be used with virtually any audio/video equipment. The JVC original Paging/Call Function allows for convenient voice communication from the base station to the headset user. Large 40mm diaphragms insure high quality sound. A self-adjusting, comfort fit head band makes them easy to wear. This wireless headphone features automatic on/off as well as automatic charging when returned to the base, and also it comes with auto tuning feature. Rechargeable Ni-Cad batteries are included. Includes Headphones with Base, Rechargeable Ni-MH batteries, AC adaptor, Connection cable x 2, Plug adaptor. Paging/Call Function - for paging/calling headphone user from base station (trasmitter); PLL-stabilized transmission technology; Extended reception range of 164 feet; Auto tuning; On stand charging; Auto power on/off trasmitter; Frequency response: 25 - 13,000 Hz; 40mm drivers for high quality sound; Weight: 8.82 oz.; Battery life: 10 hours; Power requirement: Rechargeable Ni-MH battery x 2 (included).