Tom Kuehn invented the Safe Lock device after the terror attacks in 2001, but since the mass shooting at Sandy Hook Elementary in Connecticut last year, he's been getting more orders.
And that includes the Olympia School District, where he used to work.
It was installed in the doorway of fourth grade teacher Kim Daughty's McKenny Elementary classroom a few weeks ago. It prevents teachers from having to fumble for a key when they need to go into lockdown.
"Which one is my master key? Which one is my outdoor key?" she said. "And then I would have to go outside my classroom lock my door and make sure that it's locked."
Now, teachers just flip a lever installed at the door jam and the door automatically locks, keeping intruders out.
"It makes me feel safer because I don't really like when the teacher goes out of the classroom," said fourth grader Lizzie Flink. "It makes me scared like something's going to happen."
During the shooting at Sandy Hook Elementary in Connecticut this year, teachers couldn't lock the doors without keys.
"Our goal is that staff and students are in a safer mode," Kuehn said.
Kuehn said he went through seven prototypes, before settling on one that would fit different configurations of doors. It's already installed in hundreds of school districts in 46 states.
For more information, check out globalinnovationsco.com