The JK Armament RPX 9K in Black is a short, booster-ready 9mm suppressor from the RPX family (JK Armament part no. JK155RPX9K). It trims the RPX design into a compact modular can for 9mm pistols and pistol caliber carbines, with a 1/2-28 piston and booster installed. The black finish blends in on the slides and receivers most shooters already own. A high-flow flash-hiding end cap comes on it, and the baffle stack lets the owner set the length and weight. It suits range shooters and home-defense owners who want one compact can for a threaded 9mm and a carbine.

Key Specifications

• The caliber rating is 9x19mm, which JK Armament also lists for .38 Special, .357 Magnum and all smaller pistol cartridges.
• Mounting is a 1/2-28 piston and booster included, the common pattern on threaded 9mm pistol barrels.
• Length is 3.3 to 7.25 inches with the mount, depending on the baffle configuration.
• Diameter is 1.55 inches, slimmer than the Pro-Kor tubes.
• Weight is 7.5 to 13.1 ounces with the mount, set by how many baffles are installed.
• Construction is Ti-6Al-4V Grade 5 titanium and 7075 billet aluminum, a mix that balances strength and weight.
• The finish is black with Type III hard anodize and Cerakote, which resists wear.

Frequently Asked Questions

Is this the black or the FDE RPX 9K? This listing is Black. JK Armament also offers the RPX 9K in FDE.

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.

What comes installed on the RPX 9K? A 1/2-28 piston and booster plus a high-flow flash-hiding end cap come installed, so it is ready for common threaded 9mm pistol barrels.

Buy the JK Armament RPX 9K Modular 9mm Suppressor, Black

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 JK Armament‘s suppressors and suppressed firearms lineup and our Lubbock, Texas team will handle the transfer.