Check out this DSAL-2 125db door stop alarm that not only prevents anyone from opening the door, but emit an ear piercing alarm to boot whenever somebody forces their way inside. The inclusion of an adjustable movement sensor is great as you no longer need to worry about every single bit of movement triggering the alarm whenever you’re not around at home. An On/Off switch has also been conveniently placed to prevent it from going off in your luggage while you’re traveling, although it would make better sense to just remove the battery. It will cost you $15 to pick one of these up.

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