The only 5 channel device available. All channels allow fully-independent treatment setups as well as ComboPlus technology offering Ultrasound in combination with Interferential, Premodulated, Biphasic, High Voltage pulsed stimulation, and Russian stimulation using any available electrotherapy channel. Dynatron 25 Series models offer 1, 2, and 3 MHz frequencies for the greatest flexibility in depth of treatment. Choose 1 MHz for deep treatments, 2 MHz for moderate depth, or 3 MHz for superficial depth.