Wickes Building Alarm Tear Down - What's inside?

Acquired this from the side of a property and wanted to see if it was a real alarm or just a visual deterrent. Turns out there was a fair bit of electronics inside!

[@Rhythmman14]

i love these external sirens, i have the yellow version that comes with the friedland version, still works perfectly 8 years later, makes a lovely row when it goes off!