A month after bump stocks figured in the worst mass shooting in modern American history, Congress has produced a short stack of legislation, but no new restrictions, on gun accessories and other firearms products that skirt existing laws.

While lawmakers idle, gun companies are expanding their offerings of barely legal products. Springfield Armory became the latest to do so with the November 1 release of the Saint AR-15, a pistol equipped with a “forearm brace” that a shooter can easily use as a stock. Such a use would convert the weapon into a de facto short-barreled rifle, without requiring buyers to register their purchase with federal government and pay a $200 tax, as mandated by the National Firearms Act.

As Springfield rolled out its pint-sized AR-15, leading bump stock maker Slide Fire notified customers that it was taking orders on a limited supply of its controversial devices. The Texas-based company had stopped selling the items shortly after reports zeroed in on the Las Vegas shooters’ likely use of bump stocks to accelerate his deadly bursts of gunfire. Major retailers such as Walmart and Cabela’s also pulled bump stocks from their online marketplaces. Other stores quickly sold out. Springfield’s AR-15 pistol and the fresh batch of Slide Fire bump stocks join a market for nearly illicit gun products that has remained readily available from large and small retailers in the wake of the Las Vegas mass shooting. A review by The Trace found at least a half dozen devices, designed to flout federal gun restrictions — or come right up the edge of legality — on offer. They include:

1. Polymer80 unfinished Glock pistol frame

The pistol frames are what’s known as an “80 percent” firearm. Manufacturer Polymer80 produces the part of a pistol that the ATF considers an actual firearm for the purposes of regulation. But because it is sold with excess plastic left in the handle, it doesn’t technically qualify. That means the ATF can’t trace a Polymer80 gun if it is used in a crime. The frames can also be sold without background checks.

Transforming the Polymer80 into a functioning weapon requires that the buyer remove the excess plastic with his or her own tools and add parts like a trigger.

Where sold: Brownell’s said in a press release on October 11 that it would “exclusively” sell certain models of the Polymer80. The CEO of the chain, Pete Brownell, who is also president of the National Rifle Association Board of Directors, touted the frames as ideal for hobbyists who like a bit of do-it-yourself fun. But nearly identical products sold by another company, Ghost Guns, are clearly marketed on the basis of their lack of a serial number, and the fact that their sale is totally unregulated.

Two online gun sellers, Midway USA and Rainier Arms, also stocks Polymer80 Glock frames.

2. Pistol stabilizing braces

Springfield Armory followed the lead of Sig Sauer and at least two other companies in manufacturing a “stabilizing brace” attachment for AR-style pistols. As marketed, the part straps the gun to the shooter’s forearm to reduce shaking. But the brace can also be used as a shoulder stock, steadied by the shooter’s body so they can aim the weapon like a rifle, with their eye right against the sights.

Doing so turns the weapon into a short-barreled rifle, a weapon that is more easily concealable than a full size rifle and more powerful than a pistol. Short barreled rifles must be registered with the ATF under the National Firearms Act, but because stabilizing braces aren’t designed for rifle-style aiming, guns equipped with the accessory can be sold without registration.

Where sold: Brownell’s sells the braces, along with competitors Cabela’s, Walmart and Rainier Arms.

3. The RONI STAB

The company’s original product, the RONI SBS, adds a stock and barrel extension to a typical semiautomatic pistol, which improves accuracy. Because the accessory turns the weapon into a short barreled rifle, it must be registered under the NFA.

The RONI STAB, like the Sig Sauer SB15, also uses a brace to get around National Firearm Act requirements.

A company spokesman says in a promotional video that the product is a way to avoid the paperwork, cost, and wait time that come with registering one’s weapon before going on to note that “the Roni STAB is intended to be used only as designed.”

Where sold: Online dealer Cheaper Than Dirt sells the STAB.

4. The Mossberg Shockwave

Legacy gunmaker Mossberg, best known for selling traditional hunting shotguns, is also selling a weapon that just qualifies as legal under the National Firearms Act. In January, Mossberg released the Shockwave, a “personal defense” shotgun that is half an inch longer than the minimum required length.

Short barreled shotguns without shoulder stocks and less than 26 inches in length are regulated under the NFA because they are easily concealed, and were favored by criminals at the time of the law’s passage.

The product debuted to press explaining that yes, it is indeed legal. In Texas, legislators passed a law to allow the sale of short shotguns not registered under the NFA.

Where sold: Brownell’s carries the weapon, as do online retailers Bud’s Guns and Palmetto State Armory.

5. The Black Aces Tactical

Like the Shockwave, the Tactical barely exceeds the ATF’s minimum length for short barreled shotguns, measuring 27 inches long. Its barrel is only 8.5 inches long.

The Black Aces gun also adds a forward pistol grip, a magazine for additional ammunition capacity, and a forearm brace that can easily be used as a shoulder stock that is similar to the RONI Stab and the Sig Sauer SB 15. Should the owner actually use the brace as a stock, shouldering the weapon when firing, it would technically become an illegal short barreled shotgun, if not first registered with the ATF. The agency regulates shotguns with stocks if the weapon has a barrel shorter than 16 inches.

Where sold: The shotgun isn’t sold by any national chains, but is available at dozens of smaller outlets around the country.

6. The Binary Firing System

Nearly all bump stocks, trigger cranks, and similar products for accelerating a semiautomatic rifle’s rate of fire have disappeared from online sellers — with one exception. The Franklin Armory Binary Firing System doesn’t allow a shooter to fire as fast as with a gun equipped with a bump stock, but it can still double a semiautomatic’s rate of fire. It works by shooting twice for each full cycle of the trigger: once when the shooter pulls the trigger, and again when it is released.

Where sold: Franklin Armory’s trigger system is sold by Optics Planet and Botach.com, though the latter store is out of stock. Online auction behemoth eBay also allows the sale of binary firing systems, even though it has banned bump stocks for years.