I've carried my ARC AAA LED light attached to my keychain with a pile of keys every day since the end of 2005 - 6.5 years - and it looks exactly like it did the day I got it. Its one tough light.

Now I do have to say that I was concerned about damaging the LED "bulb" in my pocket so I bought a plastic tube end-cap that almost slide over the tip of the Arc and then I sanded it down until is slide over the tip without much force. That worked well ... but I don't know if it was necessary.