The PK-21N30WQ is a miniature piezoelectric buzzer designed for audible signaling and alarm applications across a wide voltage range. It operates from 1.5 to 30 VDC with a rated voltage of 12 VDC, consuming a maximum of 12 mA at rated voltage and producing a constant 3 kHz tone with a sound pressure level of 80 dB minimum at 30 cm. The device features an ABS plastic housing (UL94HB rated, black color) with 28 AWG lead wires and weighs only 3.2 grams, making it suitable for compact electronic assemblies. It is rated for operating temperatures from -20 °C to +70 °C and storage temperatures from -30 °C to +80 °C, with wave soldering capability at 245 ±5 °C for 3 ±0.5 seconds or hand soldering at 350 ±20 °C within 5 seconds. Common applications include alarm indicators, notification systems, and audible feedback in consumer electronics, industrial controls, and portable devices.