Specification: 1) PLL technology 2) multi-directional transmission 3) frequency: 863.1MHz-863.5MHz or 912.5MHz-914.5MHz. 4) frequency range:20Hz ~ 20KHz 5) distortion: <=0.5% 6) S/N Ration: > 60 dB 7) frequency range:20Hz ~ 20KHz 8) R/L channel separation: >30dB 9) transmission range: 100 meters 10) power supply (transmitter): DC12V 11) power supply (headphone): 700mA/H rechargeable NI-MH battery Feature: 1. ultra-high frequency, high fidelity 2. ultra-low distortion 3. transimission through walls, floors, ceiling etc. with ease 4. strong stereo sound 5. strong anti-disrupption capability 6. high power output 7. low FCC 8. stable performance 9. designed for EU&US markets 10. simple&elegant look widely applicable to PC, TV, DVD VCD, MP3, MP4 and other major audio sources