wants to be an switched out & not the speaker one...
test- remove battery from panel touch the red wire to the red terminal & the black wire to the black termial
Not that I buy 'em, a trade discount of 19.5% on the leading security wholesalers web portal still leaves ebay £21.60 cheaper....
I'd assume the equipment the installer has spec'd is a reflection on what he's thinks you'll spend, eg there's no way you'd pay for webway