Have you ever been rousted out of bed by an unexpected, urgent knock at your door? Instantly, your heart races and you hurriedly react. If this has happened to you, I hope it was a minor event that you handled in stride. In this age of rampant crime, including home invasions, the security alarm business prospers as people attempt to protect themselves and their property. Sophisticated systems are now available to let you know who is at your door, even when you are not at home.

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