The Umarex - Elite Force - Amoeba AS-01 Striker Rifle in Olive Drab.
This gun is built around modularity, functionality and minimalism. With everything that you need, and none of the that you don't. It's compatible with AEG springs, has a metal receiver, bolt barrel assembly, and adjustable polymer chassis. The butt pad is also adjustable with a cheek riser and grip front strap. A ambidextrous magazine release and loaded chamber indicator, with a direct feed 55 round magazine. The hand guard is interchangeable and the hop-up is adjustable.