Features:1. The MODE button can adjust the performance sound. There are Clean original sound, Flanger & Mater heavy metal with corresponding indicators.2. the UHF wireless transceiver distance is 15 meters (different environments, the distance will be different); with ID matching function, 10 variable channels, no interference, multiple sets of use in the same area;3. the launching cassette display, with volume adjustment push-pull button, with D3.5 output jack, built-in amplifier, can be connected to the guitar speaker (Guitar port) or wired headphone output, can work independently, especially suitable for pre-show or personal warm-up rehearsal ;4. the power supply: Built-in lithium battery, there is a USB (Universal Serial Bus) charging port, full battery life up to 5 hours, there is a corresponding charging, low power indicator.5.certification: ROHS, the United States FCC, European CE, Bluetooth BQB, Japan TELEC; Key parameters: Work channels:10 Frequency response:50-18k Hz Power supply: Built-in Li battery Latency:3ms Working Distance:about 50 feet Battery life: Transmitter-about 3 hours Receiver-about 6 hours Packing List:1*K38E transmitter 1*K38E receiver 1*USB charging cables 1* User Manual 1*PU leather bag Note: Click: Instruction Manual