I keep about a dozen of these stickers in the admin pouch on my chest rig at all times. They're handy to slap onto fences, gates, doors, etc. in order to warn folks off while I'm working. Do you think it helps? Meh, sometimes, but not consistently. In fact, in a couple of cases, it seems to have attracted attention from nosey, know-it-all kids. But I figure my liability will be covered if they get themselves eaten.