by peterku Double barrel. Magazine - remote battery pack is engaged in rear section. Technology designed inside body allows to use this piece only within 200 meters range. This limit determine to use this equipment on space stations.
For those who are curious, the company in question is Shuff's Parkerizing. They're known for restoring, tuning, and modifying U. surplus rifles, most particularly the Garand. They're best known for their "Mini-G" Tanker Garand mod.