No audio suppressor was produced pending a viable Answer to the inherent sonic crack produced by standard 9mm Parabellum cartridges. There were a few capabilities on serial quantity 2 that were various from foreseeable future production types. The weapon was full-automatic only, plus the grip backstrap was fabricated from aluminum. https://stephenblkyi.ivasdesign.com/38392254/the-2-minute-rule-for-mac-10-guns