Transmitter part Carrier frequency:2.4GHz. Bandwidth reaching distance:longest about 30m(98 ft). Transmission frequency band:10~24000Hz. Power:DC5V(with AC adapter). Size: 185W ~ 35.5H ~ 113.5D (mm). Weight: about 223g Headphone parts Carrier frequency:2.4GHz. Playback frequency:10~24000Hz. Power: DC 2.4V(Rechargeable batteries~2) or DC 3V(AAA alkaline batteries~2). Charging time:about 3 hours. Duration:about 15 hours(Rechargeable batteries). About 20 hours(AAA alkaline battery). Weight: about 227g (including rechargeable batteries). Size: 195W ~ 220H ~ 76D (mm). Only Japanese manual. Noise canceling: Not supported Surround: correspondence Description 7.1ch Dolby Digital, Dolby Digital Surround EX, Dolby Pro Lotic IIx, DTS, DTS-ES, MPEG-3, AAC. 40mm Dinameter headphone driver.