What is this yellow box on our house?

[Bizzarely]

Sorry, if it's a common thing and a very dumb question. But what is this? We aren't from UK so no idea what this might be. It's connected to our mains, no clue where the switch is. There are tiny red lights inside as in the picture. No logo, no company name,...
Thanks

Alarm, or dummy alarm

Burglar alarm?

House alarm.

Should have a control box inside house somewhere where you put pin in to set it altho if you don't know the pin already then you can't reset it.

Thanks. Strangely, haven't found anything which looks like a keypad to control the alarm inside. Also no brand name, nothing. I had considered dummy alarm but it's actually connected to our mains 🤷‍♀️.

Could still be a dummy, and the mains powers the flashing light to make it look real. Or the keypad is hidden somewhere, shouldn't be too far inside the house though as you need to access it easily before you leave and on return.

Looks pretty ancient - old alarm that was taken out?

There could be a battery panel for it in the loft?

Is there a box in the airing cupboard?

I've got a similar looking alarm on my house, although it doesn't appear to be connected to anything. Landlord told me it's an alarm which is apparently activated by a key (not a keypad, an actual key) in a thing in the hallway. Only the key is long lost so it's just a keyhole in a panel in the hallway

We have a dummy alarm box on our house - it's actually a fully functional box with multiple 'ights, and actually has a siren inside too (if you disconnect andnf reconnect the power it sounds for a couple of seconds while it boots up or whatever).

It's basically a fully functioning box except that it's wired to a DC adapter instead of an entire alarm system!

Thanks, looks like it's some kind of alarm system then. Dummy or not, if it deters burglars...I am good with it 😊. I will leave it alone.