The DUODYNATOR® 119 is a product of continuous technical improvements that focus on medium frequency currents that patients find comfortable. The DUODYNATOR® 119 has two channels. It can be utilized as an interferential device where the required stimulation effect is obtained by the transfer of two medium-frequency currents that have different frequencies to the deep part of the tissue. It can also be used as a 2-channel MF-device where the patient can be treated by the user at two points with the use of two independent channels with current waveform and intensity that is chosen by the user. It can also be used as a low frequency unit that offers standard electrotherapy currents.