This version is equipped with dual 3.5mm external key interfaces, with one as input, supporting external direct keys (heavy keys), bug keys, or automatic keys (single or double paddle). (The old-fashioned heavy-duty cw key plug is 6.5mm and requires a conversion connector to be used); One is used as an output to connect to other devices such as radio stations. Using dual color cw key indicator lights to distinguish between beeps, the code can be played in a three in one sound, light, and character combination during listening training, making the practice more intuitive. The front speaker has clear sound, the volume is linearly adjusted by the mechanical knob, and the pitch is digitally adjusted. There is also a headphone jack that allows for silent practice with headphones, which feels better. Powered by lithium batteries and integrated with a charging management chip, it can be used safely and with confidence. Equipped with Type-C USB charging port, supporting mobile phone charger charging. Equipped with a 2.3-inch LCD screen, adjustable contrast, and white backlight with adjustable brightness, the image is large and clear. Colour:blue Material:plastic Equipped with a 3D printed sealed shell, it is beautiful and simple. The external dimensions of the exercise device are about 95x70x23mm, with a compact size and easy portability, making it very suitable for radio enthusiasts to learn Morse code anytime and anywhere. Adopting a Chinese interface, with complete functions, intuitive operation, and convenient use. The main functions include CW input practice, radio decoding, listening test, phrase query, character encoding query, etc. You can set the sound switch and tone, clap practice speed (wpm), listening test speed (wpm), cw key type, screen contrast, etc. Buttons and Functions: Menu key: In function mode, it calls up the main menu; In the setting mode, it returns to the main menu; In the main menu mode, it is to exit the menu and return to the practice mode. Selection key: When in menu state, it switches between menu items; When in practice mode, clear input content and reset statistical data; When setting, it is a rotation of setting items. CW key: Confirm selection in menu state; During practice, it is using cw keys; During listening training, it is to start/pause (short ) or generate a new test (long ); When setting, adjust the data value. Due to different batches, there may be differences in product appearance and printed text, which not affect use Package Contents: 1 * Morse Code Trainer 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.