the professional version has a built-in CW audio decoder board, which can be connected to shortwave radio stations to decode CW's Chinese and English audio signals and display them on the host screen. Built-in 2500mAH high-capacity lithium battery, which can be continuously standby for up to 20 hours. It can be used as an exerciser or as a sending device for sending reports. Support Chinese and English menu interface friendly, can customize the exclusive boot interface Type:Professional Version Colour:Black Material:aluminum alloy Package Contents: 1 * Morse Code Exerciser 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.