Rugged Suppressors Rugged Universal 3 Lug Mount 1/2x28 Black. This is a perfect solution for mounting 9mm rated suppressors like the Alaskan360 Sub9 or any other HUB/universally threaded suppressor onto subguns and pistol caliber carbines. This does not work on the Obsidian45 or Obsidian9. Specifications for Rugged Suppressors Rugged Universal 3Lug Mount: Manufacturer: Rugged Suppressors Caliber: 9mm Luger Color: Black Threads per Inch: 1/2x28 Package Contents: Rugged Suppressors Rugged Universal 3Lug Mount Rugged Suppressors RU3: Rugged Universal 3Lug Mount 1/2x28 Black