The DM901 sounding electric key adopts European and American style design, exquisite, scientific and beautiful, easy to operate, with sound output and keyed output. It is equivalent to the oscillator exercise function and can be used with a radio or exerciser according to different environments. It is a powerful tool for radio enthusiasts to learn and participate in CW competitions. For people: Radio lovers learning, Signal training collection, Give children gifts to cultivate hobbies Body size: length 130 x width 66 x height 44mm (without protrusions) Weight: 0.2KG Output interface: 3.5 dual-channel Buzzer power: 0.5W Internal battery compartment:2 x AAA battery(batteries not included) Due to different product batches, the appearance , which does not affect the use. Colour:Black Material:ABS Package Contents: 1 * DM901 Sound Key Kit 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.