Rat Worx Steyr AUG Suppressor Adapter (M13x1 LH to 1/2-28)

The Steyr AUG and AUG A3 M1 ship with an M13x1 left-hand metric muzzle thread, which was the European service rifle standard when the AUG was designed in the 1970s. M13x1 LH is not used on US-market suppressors or aftermarket muzzle devices, which means the AUG cannot accept a standard 1/2-28 RH suppressor mount, brake, or flash hider without an adapter.

The Rat Worx Suppressor Adapter is a CNC-machined thread adapter that screws onto the factory M13x1 LH muzzle and provides a 1/2-28 RH output. Once installed, the AUG accepts any standard 5.56 muzzle device or direct-thread or QD suppressor mount. The adapter is precision-machined for concentricity and timed properly so muzzle devices index correctly. Installation is straightforward and the adapter can be removed if you want to revert to the factory configuration.

For shooters running a suppressor on the AUG, this adapter is mandatory. It is also the gateway part for replacing the factory AUG flash hider with a more effective brake, compensator, or muzzle device of the shooter's choice. Note that the AUG does not ship with a self-timing muzzle thread or shoulder, so muzzle devices may need a crush washer or peel washer for proper alignment depending on the device. The adapter does not change the AUG gas system; suppressor users may still need to adjust the gas regulator for back pressure.