Major online marketplaces that have policies forbidding the sale of gun parts and accessories are still hosting listings for pistol stabilizing braces.

Until Thursday, several braces were listed for sale on Google Shopping, the tech company’s commerce portal, despite a policy prohibiting the sale of parts or components that “enhance the functionality of a gun.” Google removed the listings after The Trace sought comment.

These listings persisted even as the accessories, which are intended to increase the accuracy of AR-style pistols by strapping onto a shooter’s arm, came under scrutiny after a firearm fitted with one was implicated in the mass shooting on March 22 in Boulder, Colorado. On April 8, President Joe Biden announced an executive action directing the Department of Justice to regulate the items under the National Firearms Act, prohibiting their normal sale and requiring them to be registered with the federal government.

In December, the Bureau of Alcohol, Tobacco, Firearms and Explosives withdrew a request for comment on a proposal to include stabilizing braces under the National Firearms Act after 90 House Republicans sent a letter criticizing the proposed regulation as “ambiguous and malleable.” 

Google is not alone in hosting listings for stabilizing braces. One has been listed for four weeks on Facebook Marketplace, which also bans sales of firearm parts. The Indianapolis-based seller categorized the controversial gun accessory as a health-care product.

Multiple users on Etsy were also offering the braces for sale, including one 3D-printed model available for only $38. The site’s policies forbid sales of gun parts and “accessories for assault-style weapons.” Etsy removed at least two listings after being contacted by The Trace and suspended the account of the 3D-printed brace seller. That seller, who identified himself as Greg Gaskins, had previously been suspended in 2020 for gun policy violations, according to an email notification of suspension that he provided to The Trace.

A Google spokesperson told The Trace that “we enforce our policies vigorously and immediately remove violating listings when we find them,” and confirmed that the brace listings had been taken down.

Facebook did not respond to a request for comment.

An Etsy spokesperson told The Trace that stabilizing braces are included in the site’s prohibition on gun accessories, and that listings that violate policy are identified using “a combination of automated and manual tools.”

Two of the three braces that were listed on Google are made by SB Tactical, the manufacturer that invented the items and attained regulatory approval for them from the ATF in 2012. The Facebook listing is also for an SB Tactical brace.

A Facebook Marketplace listing for a pistol stabilizing brace.

Tech companies have repeatedly struggled to police prohibited guns and gun parts in their marketplaces. Following the 2018 mass shooting in Las Vegas, Google removed listings for bump stocks, and after the 2019 shooting in Dayton, Ohio, it unlisted 100-round drum magazines similar to the one used by the gunman. 

Facebook, meanwhile, has struggled to crack down on users’ workarounds for its ban on gun sales. Last year, The Trace found that sellers were advertising gun cases on the platform and then offering actual guns for sale in private messages. And The Markup reported in February that Etsy, better known for handmade crafts, also had a thriving market for custom-engraved high-capacity gun magazines.

This story has been updated to include comment from a Google spokesperson.