For those older Styer AUG that do not offer out-of-the-box a full Picatinny rail on the receiver, Corvus Defensio offers its own solution – for the A2/USR, M1, and even the A3. We receied the Receiver Rail version for our older A2, that features the reinforcement bump, or “hump”, on top of the polymer stock. It is very easy to install and adds many features to the AUG: read on to find out!