Clinical Electrotherapy - Amrex Ultrasound/Stim Combo - US/752 (High Volt), 1.0 and 3.3 MHz with 5 cm head and QuickConnect Transducer : Dual channel HV with variable frequency 1-160 pps, reciprocal and ramped surge (2-90 seconds), patient interrupt switch and adjustable "on/off". 20 watts, pulsed or continuous output modes.