No power supply required

Compact structure, light weight, easy to carry

Strong sound, low frequency

The signal is generally recognized

Shutter mechanism, provide signal selection

The hand-cranked siren does not require a power source and is traditionally used for military purposes. It can be used in places without power support, such as outdoor open area, military camps, border posts, civil defense, mountain rescue, forest areas, coastal defence, fire or flood warning, etc. It can provide convenient and effective warning signals.

By shaking the handle to make sound, the loudness of the alarm sound depends on the speed of the handle shaking, and a shutter shutter mechanism is set in the sound window to quickly adjust and close the sound window to change the sound level and generate different signals.

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