Product Name : Electronic Buzzer;Model No. : SFM-27;Sound-making Type : Continuous Sound;Rated Voltage : DC 3-24V Rated Current : less than 12mA;Sound Pressure : more than 95dB;Operating Temperature : -20C to +45C Body Diameter : 30mm / 1.2inch ;Overall Size : 47 x 33 x 25mm / 1.85inch x 1.3inch x 1.0inch (L x W x H);Mounting Hole Diameter : 3.5mm / 0.138inch Mounting Hole Distance : 38mm / 1.5inch ;Wire Length : 11cm / 4.3inch ;External Material : Plastic Color : White;Weight : 44g; Plastic housing, DC 3-24V working voltage, black and red 2 wire, convenient for wiring. An perfect item for industrial use. Package Content: 4 x Electronic Buzzer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.