Features: Adopts SMT technology, strong anti-interference, anti-noise, stable signal. The effective distance between the wireless micophone and receiver is about 30-50 meters. USB receiver with 3.5mm audio cable and 6.35mm to 3.5mm adapter is compatible with outdoor speakers, amplifiers, multimedia classrooms sound box, etc., plug and play. The handheld microphone set can be widely used in home karaoke, campus speech, business conference, friend party, wedding, carnival, outdoor performance, etc. Handheld microphone transmitter offers 2-8 hours of battery life using 2 AA batteries (included). The receiver is USB powered via sound system or other mobile power source. Can only plug in equipment with Mic input, can't plug in AUX input, otherwise there is no sound. Make sure you have enough power for the mic and receiver. Specifications: Frequency Range: 220MHz-270MHz Frequency Stability: 50PPM Frequency Response: 60Hz-13KHz SNR: 60dB Receiver Modulation Mode: FM Working Distance: 30-50m (in a barrier-free environment) Microphone Battery: 2 * AA bateries (Included) Using Time: 2-8 hours Color: Black Microphone Size: approx. 5.0*24.2cm/1.96*9.52in Microphone Weight: 117g/4.12oz Receiver Size: 7.7*2.6*1.1cm/3.03*1.02*0.43in Receiver Weight: 15g/0.53oz Package Size: 29.0*9.0*7.0cm/11.41*3.54*2.75in Package Weight: 260g/9.17oz Package List: 1 * USB Receiver 1 * Handheld Microphone 1 * 3.5mm Audio Cable 1 * 6.35mm to 3.5mm Adapter 1 * User Manual (English)