Place these bright and easy to read stickers on the glass doors or widows of your home or car to announce to would be intruders that your property is protected by an electronic security system. These decals are a great deterrent whether or not you actually have an alarm system. Thieves are looking for the easiest home or car to burglarize. The presence of these decals can cause them to pass by your property in search of an easier target. The decals measure 4 inches by 4 inches. Each pack comes with 4 decals that have a UV coating to prevent fading.