Features: High-quality wireless audio transmission system(transmitter + receiver) for microphone with XLR connector. 4 different frequencies raging from 5.729G to 5.820G for convenient and stable signal transmission without interruption. 24bit/48kHz high resolution audio signal and less than 6ms low delay time. Built-in rechargeable battery, lower power consumption and longer work time(transmitter 75mA, receiver 60mA). Charging by 5V USB cable connecting to power bank, computer, laptop or power adapter, very convenient. With ID channel indicator an low power warning indicator. Specifications: Brand: AROMA Model: ARC1 Channel: 4 Frequency: 5.729G to 5.820G Signal Noise Ratio: 140dB Sound Quality: 24bit/48kHz Delay: less than 6ms Max. Transmission Range: 35m(no obstacles) Charging Time: 4H Working Time: 2-4H Standby Time: 4H Battery: 3.7V 450mAh rechargeable battery(transmitter), 3.7V 360mAh rechargeable battery(receiver) Item Weight: 117g/ 4.1oz(Transmitter + Receiver) Package Size: 13 * 12.5 * 4cm/ 5.1 * 4.9 * 1.6in Package Weight: 190g/ 6.7oz Package List: 1 * Transmitter 1 * Receiver 1 * USB Charging Cable 1 * Users' Manual(English & Chinese)