The use of this headphone has been very good, and the sound from it is excellent, and we do not forget its value with its quality with this wonderful seller
At 3V, it is not loud. At 24V, it's a quite loud. It generates a 3.8 KHz tone. Current consumption 30mA at 24 V; 10mA at 3Vdc. It looks durable. Package delivered to Brazil in 20 days (Aliexpress Direct).