PITTSBURGH (KDKA) — Imagine there was a gunman inside your child’s school and a door was the only thing between him and your kid.

Round after round, he shoots, but can’t get in. That’s because the door is bullet-resistant and more schools across the country are starting to install them.

Schools like Harrington Park School District in New Jersey have them. Superintendent Adam Fried installed them in his school about nine months ago.

“This allows us to have that ability to have some time to get us into the safest places we need to be. For me that makes me sleep a lot better,” said Fried.

The doors, made by REMO Security Doors, aren’t cheap. They cost $2,500 apiece to install. A hefty price tag, for sure. However, is there a price too great to protect children?

“I wanted to find a solution to protect my kids from this unnecessary or unsafe lockdown drills,” said REMO Security Doors Founder and CEO Omer Barnes.

Barnes founded REMO Security Doors about two and a half years ago.

“You take a regular classroom, install this door, and then you create a safe room. The classroom stays the same. The door functions like a regular door,” said Barnes. “Simple lock. Lock the door in 12 points and the push of a handle will unlock the door.”

In addition, the lock is also designed so that if it’s shot, it will jam so a shooter can’t open it.

What about the window in the door?

“The glass is like the door. It’s ballistic. It will stop a gunshot. It will never shatter,” said Barnes.

The doors are made with Kevlar, but they’re not much heavier than your standard door. While they’re billed as bullet-resistant, Barnes said the company can’t claim they’re bulletproof.

“If you shoot at the same place multiple shots, eventually the bullet will penetrate,” said Barnes.

Which is why they say it’s still important to have a designated “safe zone” in each room.

“Our safety corners would be out of eyesight, right? So to your left of any doorway is your safezone in any building,” said Fried.

Everyone would stay in those “safe zones” until a police officer comes to unlock the door with a master key.

Harrington Park was the first district in the U.S. to install bullet-resistant doors. Since then, Barnes said over 100 schools across the country have installed these doors, too.

REMO is also working with churches and synagogues. In fact, Barnes said they’ve installed doors in probably more than 20 synagogues in the past nine months.

“It’s a different type of threat. Also creating safe rooms, but they have a threat from the outside unlike a school where there’s a student or past student from inside the building,” said Barnes.

Superintendent Fried said he’s already received tremendous support from other school leaders. He hopes that by sharing what his school has done, others will follow suit – turning a classroom into a fortress.

“After a while, the target gets so hardened, they look to go other places for violence. That’s a hope. It’s just a hope,” said Fried.

Barnes said he’s been in talks with two districts in the Pittsburgh area about installing the doors in their schools, though he couldn’t get into specifics because of confidentiality reasons. However, KDKA’s Amy Wadas is told one of the districts has already applied for a grant to help offset the cost.