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Other Hardware General Electronics
1

Hello,
I have to power up a siren of 12v, a battery display indicator of 3v to 12v and on/off switch using an audrino what power battery is recommended where easily available in all countries?
Do power button cell?
Or lithium battery
Or alkaline.

Please guide

2

I would think that a 12V lead acid motorcycle battery would be easily available in all countries.

3

A link or picture of the siren may bring more suggestions.