BERLIN, Md. – George Tunis III knows about stopping bullets, and the father of two is using the engineering skills he developed as a defense contractor to make classrooms safer.

Tunis is the owner of Hardwire, a company that armored vehicles and buildings during the wars in Iraq and Afghanistan. With the business overseas winding down, and inspiration from the Sandy Hook Elementary shooting in 2012, Tunis shifted his focus to schools and has developed some very innovative products to protect students from crazed gunmen, Businessweek reports.

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“Tunis came up with the idea of lining the handheld, portable whiteboards commonly used in schools with panels made from Dyneema, a polyethylene fiber strong enough to stop a shotgun blast from a foot away and light enough to wear all day,” according to the news site.

And business is booming.

Hardwire has sold the bullet-proof 20- by 18-inch whiteboards in all 50 states. Tunis’ 10- by 13-inch bullet-proof clipboard for students has also sold well.

“And after the Today show featured them on the 12th anniversary of Sept. 11, orders began pouring in from all over the country,” Businessweek reports.

“We have an incredible national asset here that we can put to work on an incredible national problem,” Tunis told the news site. “And for me, one child, one police officer – if even one is saved, we have made a difference.”

The special whiteboards, however, are not cheap.

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The 20- by 18-inch boards, which weight just four pounds and can stop multiple rounds from nearly all handguns or shotguns, cost $399, nearly four times as much as a normal, larger whiteboard. Hardwire also sells a 10.6 pound version that can stop bullets from a semiautomatic rifle for $999, according to Businessweek.

But many schools and individual teachers seem to think it’s a small price to pay for peace of mind, and $95 million in government grants for schools to develop emergency plans for school shooters is helping to fuel sales.

Colorado’s Valdez schools, a relatively small school district, spent $30,000 on Hardwire boards for all school teachers and administrators in the city in 2013, after a loaded handgun was found in a middle school bathroom, Businessweek reports.

“I like a couple of things about (the whiteboards),” teacher Sheri Beck told the news site during a training session provided by Hardwire as part of the purchase. “I like the idea that we have a tool now. And I really like that our police department was so forward-thinking in admitting this could happen here.”

A demonstration that accompanied the training in Valdez illustrated just how effective the boards are at stopping bullets.

“One expert marksman in Valdez shot 10 rounds from two different handguns into one of the whiteboards. He also fired three buckshot rounds from a 12-gauge shotgun. Even though he was only 10 yards away and some bullets were shot into the same spot, no round got through,” according to the news site.

Tunis acknowledges that the boards aren’t the perfect solution for determined school shooters – teachers could still take a bullet to the leg, or other areas – but said told Businessweek “his hope is that teachers trained and equipped to use his armor will feel enabled to charge at a shooter when he comes into a classroom.”

“You’re going to lose some,” Tunis said. “But right now you have some teachers running at these guys completely bare. (And) adding more bullets to this equation is probably not the best statistical answer.

“A bullet is going to hurt someone – from friendly fire or bad-guy fire, it doesn’t matter. The beauty of armor is that it subtracts bullets.”