Use car alarm as security help signal:
Put your car keys beside your bed at night. If you hear a noise outside your home or someone trying to get in your house, just press the panic button for your car. The alarm will be set off, and the horn will continue to sound until either you turn it off or the car battery dies.
Have your elderly parents carry them around the house or while outside. They can push the button to alert someone else in the house or neighbors in case of a medical emergency.

Similar tip: If you cordless phone has an intercom on it you can carry it while working outside and push the intercom button in case of an emergency.

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