OA Defense 2311 Pro, Single Action, Semi-automatic, Metal Frame Pistol, Full Size, 9MM, 5 Ported Barrel, Matte Finish, Black, Gray Grip, Extended Magazine Release, Enhanced Trigger, Tritium Night Sights, Optics Ready, 21 Rounds, 5 Magpul AMAG Magazines, Includes (4) Optic Mount Plate, Custom Pistol Case OA-2311-FPRO-KIT-GRY-PRT-21 The OA 2311 Pro is the full-size ported powerhouse of the OA Defense line-up. Designed and optimized for duty use and high round count range days, the OA 2311 Pro delivers maximum performance, accuracy, and reliability even under the harshest conditions.