Built-in signal alert buzzer. Built-in 0Hz, 22KHz, 13V, 18V indicator and buzzer. Signal Detection: 0hz / 22 hz. Input Range: -40dbm ~ -10dbm. Size: Approx. 13 6.5 2.5 cm / 5.1 2.5 0.9 in. Elegant appearance, easy to carry.
eBay