Fire Control Unit X01 Personal Defense Weapon Platform Now Shipping

Hrachya H
by Hrachya H
Fire Control Unit X01 SIG Pistol Chassis Now Shipping (2)

Fire Control Unit has announced that their X01 (Exo One) PDW Platform for SIG pistols is now available for purchase. The X01 is compatible with SIG Sauer P320 (full size, compact, carry, TACOPS, X-Carry or X-Five) and P250 pistols chambered in 9x19mm, .40 S&W or .357 SIG.

Fire Control Unit X01 SIG Pistol Chassis Now Shipping (6)

As you know, the serialized part (which is considered the firearm) of SIG P320 and P250 pistols is the inner chassis that contains the trigger mechanism. This solution makes the frame a non-serialized part allowing the user to have multiple frames for the same pistol. The Fire Control Unit X01 is basically another frame option for these pistols.

In order to complete the X01 Exoskeleton, you need to disassemble your SIG pistol and install its serialized chassis, magazine release mechanism and the slide assembly into the X01 unit.

Fire Control Unit X01 SIG Pistol Chassis Now Shipping (3)

The main body of the X01 exoskeleton is made of glass filled nylon. The metal parts such as the charging handle mechanism, are made of stainless steel. The unit features a top Picatinny rail as well as a vertical rail section on the rear to allow attaching SIG MPX stocks, stabilizing braces or sling mounts.

The X01 also features three handstops. The bottom one is integrated with the unit. Two side handstops are removable and have M-LOK slots underneath them.

The ambidextrous charging handle allows to lock back and release the slide in HK-style – by pivoting the handle up and locking it into the rear notch. There are also QD sling swivel sockets on either side of the unit, behind the pistol grip.

SIG MPX (top) to Fire Control Group X01 Exoskeleton

The basic regular price of the Fire Control Unit X01 exoskeleton is $449. Right now it is available at an introductory price of $399. The X-Five slide, SRD9 suppressor or manual safety compatible versions cost $50 more. You can also order it with an SB Tactical brace for additional $150.

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Hrachya H
Hrachya H

Managing Editor Being a lifelong firearms enthusiast, Hrachya always enjoys studying the history and design of guns and ammunition. Should you need to contact him, feel free to shoot him a message at

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3 of 36 comments
  • J Torres J Torres on May 01, 2018

    Make it take Glock mags!

  • I just wish Sig would sell me the Chassis separately and let me put together a pistol from scratch using the exact components I want.

    Isn't that the point of modularity to begin with?

    • PS IDE PS IDE on May 01, 2018

      @Christian Hedegaard-Schou 80% lower sig chassis =) . They are available now.