The SR-2 "Veresk" (Heather) is a Russian submachine gun designed to fire the armour-piercing 9×21mm Gyurza cartridge. It was developed in mid-1990s on the request of Russia's Federal Security Service (FSB).
SR-2 differs from most submachine guns by its gas-operated action with rotating bolt, while normally SMGs utilise different blowback principles. Externally the "Veresk" is akin to the Uzi; 20 or 30-round magazines are inserted into the pistol grip. There are two AK-style control levers on both sides of the receiver: the right one is the safety switch, the left is a fire-mode selector. The charging handle is on the right side and is fixed to the bolt carrier, so it moves during firing. The weapon has a top-folding metal stock.
The SR-2M is a modified version that also has a foldable vertical foregrip under the handguard, with a protrusion to protect the shooter's hand from muzzle blast and accidents (similar to the grip on the MP5K). Its stock can be fully folded even with "red dot" sight installed.
