Patriot IS upper chamberd in 9mm with a 10" barrle for the AR-15 platform. This is one of the most durable, quiet suppressed uppers on the market. It will fit any MIl-SPEC AR-15 lower. It does require a tax stamp. In test firing with subsonic ammo it metered as low as 100db. You can check them out at PatriotSuppressor.com or on facebook. REDACTED