24 volt
electric vehicle siren, specifically a Sirex Type Il (Part No. 3007) manufactured by Bover Products Co.. It carries the Federal Stock Number (FSN 6350-00-283-9341), which classifies it as a miscellaneous military alarm/sounding device typically utilized on vintage military trucks, utility vehicles, or armored
It works on 12 volt also but it's 1/2 as loud.
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