Last time we reported about a company trying to use a Sig Brace on a Short Barreled Shotgun. I never understood what they were thinking as there is no pistol version for a shotgun. A SBS is still a SBS or AOW.

Well another company is trying to capitalize on Sig’s success. Shockwave Technologies has made their version of a pistol AR stabilizing brace. However when submitted to the ATF, the ATF has decided that shouldering this would make the firearm a SBR. It can only be used as an arm brace, not a improvised stock.

Here are pictures of the ATF letter.

Here is a picture of an AR pistol with the Shockwave Brace installed.

I was hoping for more companies to make alternatives to the Sig Brace. However it seems the ATF is backtracking their ruling and changing their minds on future products of similar design.

UPDATE: Clarifications. The arm brace is legal as an arm brace. Not legal to be used as a stock …