Rechargeable Built-in UHF Wireless Guitar System Transmitter Receiver,Wireless transmitter & receiver set for electroacoustic musical instruments like guitar, bass, etc.  Uhf 730mhz sound transmission, anti-interface and ultra-short delay, giving you the best music sound.  Supports 4 sets of devices that work at the same time, one-to-one; and maximum transmission range is up to 50 meters.  Built-in rechargeable lithium battery, long hours of work; and comes with usb cable for convenient charging.  Plug and play, simple to use; compact and lightweight size, easy to carry.  o response range: 20Hz-20KHz  Frequency: 730mhz ultrahigh frequency  Transmission range: max.50m (without obstacle); 30m (through the wall)  Transmission delay: less than 4ms  Power supply: built-in 3.7v 600mah rechargeable lithium battery  Charging port: micro-usb  Colour:Black  Material:plastic  Size:11 x 4.5 x 1.5cm    Package Contents:  4 * Transmitter  4 * Receiver  4 * USB Charging Cable(ran color,The specified color is not accepted)  Only the above package content, other products are not included.  Note: Light shooting 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.