The Echelon 4.0 FC 9mm full size pistol incorporates Springfield Armory's serialized Central Operating Group housed within a full size polymer frame for strength and modular flexibility. Its 4 inch barrel with a 1-in-10 twist rate supports consistent accuracy, while the black Melonite finish enhances durability and corrosion resistance. The striker fired system and integrated trigger safety provide dependable operation under demanding conditions. Specifications and Features: Manufacturer: Springfield Armory Model: Echelon 4.0 FC Type: Semi-Auto Pistol Action: Striker Fired Caliber: 9mm Finish: Black Melonite Frame: Polymer Grips: Black Polymer Barrel Length: 4 in Overall Length: 7.25 in Twist Rate: 1-in-10 Capacity: 20+1 Magazines Included: 2 Magazine Description: 1 17 rd, 1 20 rd Sights: Front Luminescent, Rear Tactical Rack U-Dot Sight Type: Fixed Optics Ready: Yes Optic: Aimpoint COA Weight: 24 oz Shipping Weight: 3 lbs Safety: Trigger Safety Additional Information: Central Operating Group, Full Size Frame