PHILADELPHIA (CBS) — Caring for a loved one who wanders off can be both emotionally and physically taxing.

For one local man whose wife suffers from Alzheimer’s, turning to technology for added protection paid off.

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Authorities say the technology used to track down the missing grandmother in West Philadelphia is currently only available in three U.S. cities: Philadelphia, Boston and Miami.

The device is called SafetyNet by LoJack.

It looks like a watch and it can be worn on your wrist or your ankle. Each device has its unique transmitter and identification number.

Elijah Jones invested in the device eight months ago. That’s after his 71-year-old wife, Margaret, disappeared for three days.

Jones said, “It’s pretty scary and when I came home after not being able to find her, she was home sitting on the front porch.”

Because of her condition, Jones had already secured his house with a special alarm system and the doors with three bolts.

“All I know is that when I left to go to work, she was home,” Jones said of Margaret’s latest disappearance on Monday.

Jones says he has no idea how Margaret managed to slip out of their house undetected by her caretaker. So when he got the phone call, Jones rushed home, searched on his own for about two hours and then called 911.

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“In this specific case, within and hour of 911 being notified, the person was back at home with her family. She was found about eight blocks away from her home inside of a car,” Lt. John Walker with the Philadelphia Police Department said.

Lt. Walker credits the SafetyNet device.

Tracia Tsakiris with SafetyNet explained, “It emits a signal 24/7. The technology’s been out there for a long time. It’s the same radio frequency technology that LoJack uses to locate stolen vehicles. We’re finally LoJacking people.”

Lt. Walker added, “Philadelphia Police Department through Councilman Jack Kelly brought this technology forward about a year and a half ago.”

This is the first time, police say, a missing person in Philadelphia actually had the device on her and the system worked flawlessly.

Jones said, “Oh what a relief. What a relief.”

There is a $99 enrollment fee and a $30 monthly monitoring fee. For families in a financial pinch, makers say a financial aid package is available.

For more information on SafetyNet by LoJack:

Reported by Elizabeth Hur, CBS 3

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