This item is a piezo electronic alarm , well made of , this item is and practical use. Inside is a piezo plus the driver circuitry. Designed with 2 connctor, which is convenient for connecting. The features low voltage, low power consumption and high voice pressure. product for industrial use. Feature - Color: Black - Material: ABS and electric components - Size: 2.2x2.2x1cm - Sound Pressure Level: 85 - Rate Voltage: 12V DC - Operating Voltage: 3 - 24V - Frequency: 3000 + / - 500Hz - Drive Method: Drive Circuit Built in Mounting Holes - Well made of premium ABS material, this item is and practical use. - Inside is a piezo plus the driver circuitry and electric components. - -24V rated voltage, 2 connctor, convenient for connecting. for industrial use. - The features low voltage, low power consumption and high voice pressure. - Warm Tip: Dear buyer, Due to lighting effect, monitor's brightness, manual measurement and etc, there could be some slight differences in the color and size between the photo and the actual item. Sincerely hope that you can understand! Thank you! Package list: 2 x piezo