The PSD is designed to conveniently store a variety of items, ranging from slings, tourniquets, magazines, etc. and only limited by what the shooter can fathom / fit into the PSD. The BATFE has determined that use of the PSD on a pistol would not change the pistol’s classification to a short-barreled-rifle (SBR). The PSD fits on any pistol that uses an AR style pistol buffer-tube, 1.2” diameter is ideal, but it will accommodate most AR style pistol buffer-tubes on the market. The PSD can store the following magazine types in any size round-capacity relative to that style of magazine. The retention screws can be adjusted to ensure the PSD does not slide, or rotate on the buffer-tube as well as ensuring ideal retention strength for any stored magazines within the PSD.