The SIG Sauer P365 Custom Works fire control unit (SIG part no. 8900165) is the serialized, striker-fired heart of the modular P365 platform, built with a flat blade trigger for a lighter, more consistent break than the factory curved trigger. Finished in black, this fire control unit drops into a compatible P365 grip module and slide/barrel assembly, letting shooters build a custom P365 configuration around Sig Sauer’s proven micro-compact action. It ships stripped, so a grip module and slide assembly are needed to complete the pistol.

Key Specifications

• Manufacturer: Sig Sauer, maker of the modular, striker-fired P365 platform.
• Chambered for 9mm, the standard P365 caliber.
• Action type is striker-fired, semi-automatic.
• Trigger is a flat blade design, for a lighter, more consistent trigger break.
• Configuration has no thumb safety, keeping the manual of arms simple.
• Sold in Stripped configuration; a compatible grip module and slide are required to complete the pistol.
• Ships at approximately 0.5 pounds, in line with a compact fire control unit.

Frequently Asked Questions

Is this the serialized part of the P365? Yes, the fire control unit is the regulated firearm; it requires an FFL transfer.

Does this include a grip module or slide? No, it ships stripped; a compatible grip module and slide/barrel assembly complete the build.

Does this fire control unit have a thumb safety? No, this configuration has no thumb safety.

Buy the SIG Sauer P365 Custom Works Fire Control Unit

For shooters building a custom P365 around a lighter, flat-blade trigger, this Sig Sauer fire control unit is the serialized foundation to start from. It’s one of several handgun frame and fire-control components built for the modular P365 line. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL.