Thank you everyone for the feedback, I will give those sensors a try and see if they work, if not I have not lost anything but a few quid and a hours work I guess :)
Hi Everyone,
Sorry for being my first post here, but I have recently purchased a new home and I am now trying to update the alarm PIR sensors, mainly to make more friendly towards pets and also to bring the system up to date. I have taken a few pictures of the current sensors for reference...