The Blackout Defense KeyMo flash hider in 5/8×24 with a black nitride finish is a closed-prong muzzle device built to carry a Dead Air KeyMo suppressor mount. It is machined from 17-4 stainless steel, heat treated to condition H900 and finished in black nitride. Every 90-degree corner is undercut for a better seal and engagement with the suppressor, and a shim kit is included. This is the 5/8×24 version, and the maker states that its 5/8-24 devices are not for 9mm.

Key Specifications

• The thread is 5/8-24, the pitch that has to match your barrel.
• The bore diameter is 9.0mm (.354 inch), and the maker states it is not for use with 9mm ammunition.
• Construction is 17-4 stainless steel heat treated to H900, rated 45 to 47 HRC for through-hardness.
• The finish is black nitride, which adds lubricity, surface hardness and corrosion resistance.
• The closed-prong design reduces flash and the ping of open prongs, and a shim kit is included.

Frequently Asked Questions

Is the 5/8-24 version for 9mm? No. The maker states its 5/8-24 muzzle devices are not compatible with 9mm; the 5/8-24 bore is 9.0mm (.354 inch).

Which suppressors does it mount? It is made for Dead Air KeyMo-equipped suppressors. Blackout Dynamics (formerly Blackout Defense) is officially licensed and approved by Dead Air to use the KeyMo mount design.

Buy the Blackout Defense KeyMo Flash Hider, 5/8×24, Black Nitride

For a 5/8-24 rifle that will wear a KeyMo can, this flash hider is the mount-ready choice in black. Order it from our Lubbock, Texas gun shop for fast, insured shipping, and see our other AR muzzle devices too.