Ivor E - Interesting comment, but if I had one fitted at the time when someone broke into my car in Waitrose car park, I may have heard it or the scum may have been scared away. Also since I park both of my cars outside on my drive. If some light fingered junkie tried to break in hopefully the alarm would wake me and with me putting on the lights would scare them off. So, I think there are some uses. For the serious thief, you haven't got a hope, but for the opportunist, kids and junkies (probably the guys most likely to try and break into a Gal), it may deter (one hopes). It's that or wiring it up to the mains.