Manufacturers of the powerful and politically vilified AR-15 rifles are defending their weapons in the aftermath of a deadly mass shooting at a Florida high school.
"I think a gun's a gun," said Daniel Bogdan, a media official and graphic designer at gun maker Yankee Hill Machine. "It could be a pistol, it could be an AR-15."
"Maybe you can fire more rounds with an AR-15 versus just a pistol," Bogdan said, but "AR-15s shouldn't technically be criticized more than any other gun."
On Wednesday, a 19-year-old former student of Marjory Stoneman Douglas High School opened fire on the school's campus, killing 17 people and injuring at least 14 more, authorities said.
The gunman used an AR-15-style semi-automatic rifle, Broward County Sheriff Scott Israel said at a news conference.
Proponents of gun control have long argued that such rifles have no use in hunting and are unnecessarily powerful as home defense weapons.
"An AR-15 is not for hunting, it's for killing," Democratic Florida Sen. Bill Nelson in an interview on Thursday morning on Fox News Channel's "Fox & Friends."
But rifle makers strongly dispute that claim.
"It's how people use it," said Kit Cope, marketing director at Spike's Tactical, a Florida-based gun manufacturer. "It's also a great hunting weapon, home defense weapon and a great sporting rifle."
The AR-15, which the National Rifle Association describes as "America's Rifle," has been used as the primary weapon in a number of highly publicized mass shootings in recent years. The shooter at an Aurora, Colorado, movie theater in 2012 killed 12 and injured 70 using Smith & Wesson's version of an AR-15. And the 2012 massacre of 20 children and six adults at Sandy Hook Elementary School in Connecticut used a Bushmaster XM15 rifle, which is functionally and aesthetically similar to the AR-15.
But not all recent mass shootings involve the AR-15 or its variants. The massacre of 49 at an Orlando, Florida, nightclub, for instance, was carried out with a Sig Sauer MCX, a semi-automatic rifle that is internally distinct from the AR-15, despite its similar look.
Unlike fully automatic weapons — which have been almost completely banned in the U.S. for decades — the AR-15 and other rifles like it are semi-automatic, meaning a single press of the trigger fires one bullet.
Other manufacturers, such as Smith & Wesson, list their versions of the AR-15 under the "modern sporting rifle" category.
Of the 20 rifle manufacturers CNBC contacted for this article, only Yankee Hill Machine and Spike's Tactical agreed to be interviewed. The NRA told CNBC that it is following a "longstanding policy of not commenting until the facts are known."
The NRA claims the AR-15 is the most popular rifle in America. Semi-automatic rifles can cost between several hundred and multiple thousands of dollars; a rifle at Spike's Tactical called the "Ultimate Assassin," for instance, costs $2,430.
Sellers of the AR-15 and other semi-automatic rifles say the style is especially popular for its reliability and ability to be customized — or even built from scratch. Sales of weapon suppressors, which can reduce a rifle's noise and muzzle flash, and other accessories for AR-15-style rifles have steadily increased at Yankee Hill Machine in recent years, Bogdan said.
Cope also said the AR-15 is the most popular weapon at Spike's Tactical, though the manufacturer saw a "rapid decrease" in sales after the election of President Donald Trump.
"When it's not clear that citizens will be able to have access to firearms in the future, that's really good for sales," Cope said, explaining that many gun owners viewed then-presidential candidate Hillary Clinton as a threat to gun rights. "People are scrambling to purchase while they can."
Some gun advocates say they are not opposed to applying some level of regulation, including some form of background check or psychological analysis, to gun purchases.
In the wake of Wednesday's shooting, Cope said putting guns in the right hands can save lives. "It's a very versatile and very effective firearm, and in the right hands it can liberate the world," he said, referring to the AR-15.
"In the wrong hands, it's just as effective."
— CNBC's Brian Sullivan contributed to this story.