The helo pictured is the DAP, an MH-60L with a pair of GAU-19 50 cal gatling guns in the door that could also be fixed forward and a 30MM chain gun on the wing store. This particular shot is of the aircraft with a short wing store. With the larger ESSS the outboard could hold a 19 shot rocket pods or 4 hellfires.
Here is a photo of the 4-store MH-60K:
The DAP is used by the 160th Special Operations Aviation Regiment (the Nighthawks) and is the most heavily armed helicopter in the US Army inventory, including the Apache.
Here is a DAP with stingers outboard and mixed ordnance inboard:
DAP stands for Direct Action Penetrator, a way to keep the Apache people from coming unglued while the aircraft was being designed, since the Special Ops has no intention of employing the Apache. With the ability to carry troops, extra ammo and other goodies (think of what can be mounted on the wings!) it is an awesome fighter helicopter.