Kemo Electronic (M161) Ultrasonic Power Canon Speaker output: for piezo loudspeakers Of the enclosed type L010 max. 2 pieces are operated in parallel (1 speaker is included). Operating voltage: 12 - 14.4 V / DC Frequency: about 22 kHz (not audible to humans) frequency curve-Sine Pulse duration: approx. 0.5 sec. pulse train about 5 seconds Display: LED which blinks when the loudspeaker is connected