PISTOL: DIAMONDBACK FIREARMS MODEL DBX57, SERIAL NUMBER DBX0328, SEMI - AUTOMATIC, 5.7X28MM, OTHER, YES - INCLUDES ORIGINAL BOX, 9" Notes: The DBX 5.7 most likely refers to the Diamondback Firearms DBX57, a semi-automatic firearm chambered in 5.7x28mm. It features a compact, modern design and is known for its use of 5.7x28mm ammunition and compatibility with FN P90/PS90-style magazines in applicable configurations. Exact specifications can vary by production version, so the markings on the specific firearm should be checked before preparing a sales listing. Manufacturer: Diamondback Firearms Model: DBX57 / DBX 5.7 Caliber: 5.7x28mm Type: Semi-automatic firearm Operating system: Gas-operated Magazine: Typically uses compatible 5.7x28mm magazines; configuration should be verified Design: Compact, modern sporting/tactical-style platform Controls: Ambidextrous-style controls on applicable configurations Accessory compatibility: Designed with mounting provisions for compatible optics and accessories Finish: Commonly black, depending on configuration