Foxtrot Mike Products released the ISU-9 integrally suppressed upper for 9mm carbines. Barrel ports bleed gas into the suppressor during the bullet's travel, cutting blowback pressure and slowing ordinary 115 or 124 grain loads below the sound barrier. The gas follows an internal labyrinth around the barrel through a baffle stack and out the end cap, employing suppressor pressure to ease cycling with less mass and softer recoil while ports aligned to the lands keep accuracy.

Built on the VFM-9, it features a slim handguard with 28 M-LOK slots usable without taking the unit apart, compatibility with forward-charging or mil-spec AR handles, a transferable lifetime warranty, and a 499 dollar MSRP sold by Foxtrot Mike, Primary Arms and Silencer Shop. Company head Paul Noonan said the low cost puts advanced technology within reach of typical American buyers, and the product ships as an upper receiver only.