1.Adjustable FM Frequency Range:The frequency range of the transmitter is 76~108MHz. 2.5 Preset Stations: With 5 stations preset, you can save stations that you like.You can easily use the TUN button to manually or automatically search stations.It is convenient to immediately reach and listen to the preset station you like with the number key. 3.Two Microphone Input Modes: With built-in microphone, the pastor can walk freely in when speaking. The external microphone can be clipped to the collar to free your hands. (Note: The wired microphone is included). 4.AUX & TF Card: You can save some anecdotes of tourist attractions on your phone or TF card in advance. When travelling, you can share them with tourists through the AUX cable and TF card. (Note: The AUX cable and TF card are not included). 5.Long Working Time:With built-in 1500mAh battery, the transmitter can continually work for 6-8 hours. No frequent charging matter, it is efficient to support a long-time conference. Transmitter frequency: 76-108MHz Pre-emphasis: 50us/75us Output impedance: 50 : 70dB Frequency response: 30Hz~15000Hz RF output power: 1mW-300mW, 3levels Support mp3 format: FLAC, WAV, WMA, MP3 Support memory card: Max 32GB Power Supply: Built-in 1500mAh li- battery Working hours: About 6-8 hours Charge : DC 5V 1A Micro-USB jack Colour:black Material:plastic Package Contents: 1 x FM Transmitter 1 x Microphone 1 x USB Cable 1 x English manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.