The Sig Sauer Fire Control Unit (FCU) 9/40/357 is a factory-original pistol receiver engineered for use with Sig Sauer P320 handgun models in 9mm, .40 S&W, and .357 Sig calibers. Built with a titanium frame and finished in premium Gold Nitride, this FCU features a striker-fired design with a skeletonized flat trigger that serves as the foundation for extensive customization.
The FCU is the core component of Sig Sauer’s P320 Custom Works Studio program, enabling shooters to configure their pistol through thousands of possible combinations using different grip modules, magazines, slides, barrels, and optics. This platform allows you to build a firearm matched precisely to your requirements and preferences.
Manufactured to Sig Sauer’s exacting standards, the FCU delivers reliable performance across various configurations and maintains seamless compatibility with P320 components. The durable construction ensures consistent operation across duty, competition, and concealed carry applications.
