The Shadow Systems HS923 9mm suppressor is a modular pistol can that runs short for handling or long for maximum quiet (Shadow Systems part no. SS-9000). Shadow Systems of Plano, Texas designed it around its own pistols, and a patented front cap lets the slide of an MR, XR or DR series pistol act as the wrench. The body is lightweight 7075 aluminum with a titanium blast baffle in the highest-wear spot, under an anodized and Cerakote finish. A 1/2×28 bronze PVD piston comes with it for tilting-barrel handguns. It suits 9mm owners who want one can that can be set up compact or quiet.

Key Specifications

• The caliber is 9x19mm, for 9mm pistols with threaded barrels.
• The design is modular, so you choose the short or long configuration for the job.
• Short configuration length is 5.33 inches, with a listed 24 dB sound reduction.
• Long configuration length is 8.18 inches, with a listed 33 dB sound reduction.
• Diameter is 1.37 inches, which sets clearance around the pistol’s sights.
• Construction is 7075 aluminum, which keeps weight off the muzzle.
• The blast baffle is titanium, placed where wear is highest.
• The finish is anodized and Cerakote, for corrosion and wear resistance.
• It includes a 1/2×28 bronze PVD piston for threaded tilting-barrel handguns.
• The front cap uses a patented slide-assisted removal system, so no dedicated tool is needed.

Frequently Asked Questions

Which pistols work with the HS923? Shadow Systems lists its MR, XR and DR series, and says the 1/2×28 piston works with all threaded-barrel Shadow Systems pistols and other tilting-barrel handguns with that thread.

Do I need ATF approval to buy this? No. As of October 9, 2026, ATF no longer requires Form 4 approval, registration or a tax stamp for suppressors. It transfers on a Form 4473 with a background check through a Class 3 (SOT) dealer. State and local laws still apply.

How much quieter is the long configuration? Shadow Systems lists 33 dB of reduction in the 8.18-inch long setup and 24 dB in the 5.33-inch short setup.

Buy the Shadow Systems HS923 Modular 9mm Suppressor

As of October 9, 2026, this suppressor transfers on a Form 4473 with a background check at your Class 3 (SOT) dealer, with no Form 4 or tax stamp; state and local laws still apply. Order through Shadow Systems‘s suppressor lineup and our Lubbock, Texas team will handle the transfer, and it ships fast to your Class 3 dealer.