It's a simple device you can install right outside your front door. It's already helped save thousands of lives across the Valley, but to sign up, you have to be willing to turn in your house keys, to your local police and fire department.
We're talking about lockboxes.
Tens of thousands of people throughout the Valley have signed up for the program through their local police or fire department.
As part of Alzheimer's Awareness Month which is in June, Chandler police are encouraging senior citizens to sign up to get a lockbox installed.
In other parts of the Valley, police or fire departments offer the program to anyone who is interested. Some do have a qualification checklist.
The goal is to get first responders to you as quickly as possible.
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Picture this: You have a medical emergency. It could be a life or death situation for you.
When every second counts, you call 9-1-1, your local first responders are at your doorstep within minutes, only to find it locked, and you can't get there to open it.
"Time is of the essence in these cases," said Detective Seth Tyler with the Chandler Police Department.
It is something paramedics encounter over and over again.
"We have to break in the front door, and that is never a lot of fun. We can cause a lot of damage, and we don't want to do that," said Tim Eiden, a communications manager in the city of Peoria.
Eiden started the lockbox program with the Peoria Fire Department eight years ago. He said they had almost 1,000 residents signed up to date.
For those leery of turning in their house keys to firefighters or police officers, Eiden said they only used it in case of an emergency.
This was a relationship that had to be built on trust.
"Our keys are attached to and stay with our firetruck keys. No one else will have access to them," Eiden said.
Using the special keys, first responders can open up the lockboxes where you would have a spare key to your home stored.
Chandler police provided testimony from a senior citizen who said the lockbox might have saved his life when he got dehydrated and collapsed inside his own home.
"I stood up, and I just slid to the ground. My legs wouldn't hold me, so I pressed my wrist alarm to get to the satellite. They started to call me, and I couldn't get to the phone because it was on the bed and I couldn't get up. All of a sudden, I look up, and the firemen were in my house," the senior citizen said.
He was taken to the hospital but said the firefighters locked up after him, and left the spare key back inside the lockbox outside his front door.
"As soon as we see a lockbox we get a smile because we know we're in," Eiden said.
In Phoenix, firefighters said as soon as a person who had signed up for the program called 9-1-1; first responders could pull up the address information that gave them a key to open up the lockbox.
Other jurisdictions had similar programs.
From Home Alone Safety in Pinal County to R-U-OK in Maricopa County and Smart 9-1-1 systems are set up in Tempe and Peoria, the goal was to arm first responders with as much information as possible to help them help you in your time of need.
Peoria police said they had a total of 980 people enrolled in their Smart 9-1-1 program. Police used it at least 16 times to help 9-1-1 callers who needed assistance.
If you're interested in getting a lockbox, you should check in with your local police or fire department to find out if the program is offered in your jurisdiction.
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In Phoenix, you can call 602-262-6771 to get a lockbox. You will have to buy one, but firefighters say they are available at a wholesale cost.
In Peoria, you can get one for $50 through the fire department; you can find more information here.
In Chandler, you can apply for a free lockbox thanks to a partnership between police and the Southeast Valley Regional Association of Realtors. For more information or to fill out the application, click here.