Great quality product! I have several of these. I have a few in the house as alarms linked to windows, one on the shed. They are like "pull the pin" alarm and are very loud! Also I carry one when Im walking the dog to use if my dog gets attacked by another dog, loads of nasty dogs about today, It does work as Ive had to use a couple of times. Its very handy too as its got a bright led light on it. Highly recommended!