Compact design, easy to carry. The circuit is simple. Suitable for hand key sending exercises. The product is energy saving and environmental protection. There is no need to install batteries. Practice sending messages. TYPE-C interface allows it to be powered by mobile phone chargers, laptop chargers, mobile power supplies and even computers, free from the constraints of charging methods, and can find suitable power supply methods whether indoors or outdoors, easily coping with various usage scenarios. It supports vertical hand keys for vertical operation and horizontal left and right operation of scanning keys and mechanical semi-automatic keys. Other forms of manual electric keys are also one "device", without compromising with any manual electric keys. No matter what the operation method is, it can be easily mastered with the help of this exerciser. Power construction must be 3.5 small plug, 6.5 big plug can not be used. Colour:Green Material:PCB Package Contents: 1 * CW 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.