1, For ultrasonic beauty cavitiaton machine ( lost weight , slimming), 2, ... drive circuit drive them Our ultrasonic transducers are used for Ultrasonic lost weight machine , thin face and other ... . Frequency : 28Khz, 33Khz, 40Khz, 50W ,also has 1 mhz, 3mhz , 500khz and other piezo transducerAlso supply PCB drive ... *6170wSandwichhorn HNM-8SE-3828/4028/40 KHz±1.54300±10%≤35Ω65*7070wSandwichhorn HNM-8AS-253534 ...