Should a sticker go on the windshield of your car advertising the new antitheft device you just bought? The decision is yours, but one specialist in auto-theft prevention says: "Windshield stickers, to the amateur [car thief], might serve as a deterrent. To a professional, it may well tell him the type of device that the car has; so he would then know what quick action to take to neutralize that device. Frankly , I think the element of surprise probably has some advantage."
Some devices interrupt the flow of fuel. Some interrupt the ignition. Others lock the brakes or the steering. And some emit an audible or visible signal.
If you're in the market for such a device, this source suggests you choose one that will be most effective in areas where your car is most vulnerable.m