SIG Sauer Standalone P365 FCU

SIG Sauer

$274.99 - $349.99
(9 reviews) Write a Review
Usually ships within 1-2 business days of receiving FFL
Calculated at Checkout
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Here is SIG's OEM Standalone P365 complete FCU with all Factory SIG FCU parts and the XL flat trigger.  The FCU includes the flat trigger from the X-Series P365s and a TiN Gold coating on the FCU and trigger. The FCU will work with all P365 models, including .380 P365s. Perfect way to build your P365 from the ground-up. Custom "FCXXXXXXX" serial number (GOLD FCU ONLY, BLACK FCU HAS STANDARD SEQUENTIAL SERIAL NUMBER).

Includes: Factory SIG Sauer serialized P365 FCU, all SIG FCU parts assembled in FCU with flat trigger and receiver pin. Pistol shown for reference only. Black FCUs do not include any factory packaging. Assembly grease, oil, etc. may be present. All parts are NEW. NOT ALL OPTIONS MAY BE IMMEDIATELY AVAILABLE. PLEASE NOTE: ONLY THE GOLD FCUs CAN BE REGISTERED WITH SIG SAUER. BLACK FCUs ARE BUILT FROM EXISTING PISTOL FCUs USING SIG OEM PARTS.

OPTIONAL (checkbox): Add manual safety parts to add the SIG factory manual safety lever. See details HERE.

Barrel, Slide, Optic, Grip, Magazines, Chamber flag, etc. are NOT INCLUDED.

FFL is REQUIRED for transfer of frame. Serialized frame not available in CA unless Law Enforcement. Federal law requires that the purchaser must be 21 years of age or older to transfer a serialized frame.

For quickest shipping please have your FFL send their license to our email: We will only ship to the FFL address.

9 Reviews Hide Reviews Show Reviews

  • 5
    P365 FCU

    Posted by John on Sep 14th 2023

    Fantastic product from a fantastic company!!!

  • 5
    Gets it done!

    Posted by RangerDoc on May 16th 2023

    When I ordered this I thought I was getting a "Sig" branded FCU. What I received was in an AB Prototyping package. However, it looks just like the Sigs I already have. So I'm not sure of the origin. Having said that, its a perfect fit for my grip module and slide. It also seems to function perfectly. I haven't yet had a chance to fire it, but function testing is indeed perfect.

  • 5
    Been tough to find this...

    Posted by Nigel Lakey on May 15th 2023

    I'd been in search of this (P365 FCU, Black, Flat trigger) for some time, and with no success. My original P365 was revamped as an SAS, leaving me with almost a whole other P365 absent the FCU. Typical Sig quality, easy installation after a quick clean, smooth action and consistent trigger pull weight.

  • 4
    AB Prototype P365 Standalone FCU

    Posted by Jermaine "Jay" Harris on Apr 28th 2023

    Outstanding build quality and value at an affordable price. Great for those custom builds!

  • 5
    Solid Product

    Posted by Edward on Mar 31st 2023

    I ordered all the parts and pieces for a P365XL from various vendors. AB Prototype shipped this FCU to my local FFL quickly. In fact, it’s the first piece to arrive. It’s solid and ready to be put together. These guys are one of the few places I saw the P365 FCU in stock and hands down, the best price! Don’t sleep on it if it’s available.

  • 5
    Awesome option for setting up a p365 build.

    Posted by Brian Totten on Jan 30th 2023

    I was on the fence about buying the sig custom shop FCU or trying to find a deal on a used p365 to start my build. I wanted to save money where I could and luckily ran across the black PVD option on ABPrototype's website. This unit is much lower in price than the customer shop FCU, so when it came back in stock, I jumped right on it! The team over ABPrototype was all over my order and even answered the FFL email over the weekend! You couldn't ask for better service! The fcu arrived at my FFL in a couple of days, and I picked it up with no issue. It met all my expectations, and I felt like I got a deal after all was said and done. Thanks, AB Prototype Team!

  • 5
    365X FCU

    Posted by Roman Rex Ricafort on Nov 30th 2022

    The best product made by Sig now I can completely Customize a a new Sig Variant handgun

  • 5
    P365 FCU Black with Flat Trigger

    Posted by Mac on Nov 30th 2022

    Excellent communication and even personal emails regarding my local FFL’s license. They let me know when the information was acquired and when the item shipped. Fast shipping and the product was exactly as pictured and described. Product works perfectly. Will be a return customer.

  • 5
    Was perfect

    Posted by Andrea Miles on Mar 23rd 2022

    This fit perfectly! Service and delivery was fast.