(1) Frequency range: 87. 7 - 107. 9Mhz (2) Audio frequency range: 50 - 15, 000Hz (3) Operating range: 10 - 30 feet (4) Preset 4 channels (5) MP3, CD, PDA, iPod, personal computer, vehicle TV, game boy, and Vehicle navigation equipment compatible (6) Recharge circuit built in (7) Power and frequency LED indicators (8) Power Supply: Tow AAA battery or rechargeable batteries via using EXT. DC