Hi Chloe, very hard to tell exactly how old it is, i doubt the manufacturer would or could be bothered to tell you either, Why? because there is no money in it for them. Please be careful with Alarm companies, and this applies to everyone who reads this post. NSI companies will charge you a fortune, all so you can have a 10% discount on your home insurance. I own a SSAIB Alarm company, equally good with Insurance.
By the way, stay away from the company who's picture is below your post, they are Incredibly expensive,
Anyway if i can help you or others in any way please feel free to give me a call.
J 07842 480037
J
June 2009