this product is great. its cheap and it functions well. for me i installed it myself, and there are sites you can google to do yourself. it took me a day to do. the chirp doesn't sound loud but the alarm itself if set off is very loud. and depending on the size of your vehicle the vibration sensor mite need tweeked. but love it, and still have my system. which is the reason why i bought this. great theft deterent.