The RF Detector & Personal Alarm G718 is great for you, the device has 3 functions RF Detect dynamic range:> 73db. Alarm Sound: 130db. 1 User manual. Optical lens: special special filter. Digital 6 Levels Sensitivity: Turn on the LED 1 to LED 6 to indicate the sensitivity level 1 to level 6, press top and down button to adjust it.
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