Clinical Electrotherapy - Dynatron Soundhead for Solaris Plus & 25 Series - 5 cm2 : The only Ultrasound devices in the industry offering 1, 2, and 3 MHz frequencies for the greatest flexibility in depth of treatment. Soundhead is compatible with Dynatron Solaris Plus, Dynatron 25 Series combo units and the portable Dynatron Ultrasound unit. Patented three-frequency ultrasound - 1, 2, and 3 MHz - available to offer the greatest flexibility in depth of treatment. Additionally, the unit offers the benefit of head warming. At less than 2 lbs., the unit is easy to move around, yet reliable for any rehabilitation or hospital setting. The two-year warranty ensures customer satisfaction.