I have upgraded my alarm, which is why I am selling it. The batteries are old and in my opinion need to be changed. The two red lights started flashing together from time to item and sometimes just one at a time, which I think it is to do with the main battery (see the photos) Please make sure this siren is compatible with the devices you want to use, as no return is accepted. All the technical information can be seen in some of the photos taken from the operating manual. I have provided many photos to best describe the item, so you know what you are exactly buying. The batteries connections have been disconnected after getting the photos.
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