If it's visible, I doubt it would even chirp when hit with a hammer. Fire a concrete nail through it and I guarantee it wouldn't. Its visibility is its weakness. Scare off some kid... maybe, dissuade a bike thief... I doubt it very much.Let's face reality, if someone wants your bike, and waits around long enough, they're going to get it no matter what you spend on an alarm or lock. Nothing will get in the way. With that said, I purchased an inexpensive 113 dcbl remote alarm. Not very loud, but a a good loud warning chirp if you bump it or try to move it. Let me say this, that warning chirp and alarm sound just "may" scare off the would be thief or call attention to it. The way I look at it, it's better than nothing. I attached it to the cross bar with plastic ties that come with it. I got it on Amazon for $14.00.