This is a good devive for new comers in electro-play. It offers a good fonctionality for a reasonable price. It is sometime difficult to tune it when both channels are active. You may also get bored by its waveform capacity limitation after a while and this will be time to switch to something more serious like the Erostek ET-312 that I personally enjoy and recommend. Note that the unit has a security timer. It will stop automatically after 20mn.