Sig Sauer P320 Pro 9mm XRY3 ROMX 3.9" COY Handgun - Model 8901569

The Sig Sauer P320 Pro 9mm is a factory-built slide assembly designed for shooters who want modern reflex-sight performance without sacrificing iron-sight versatility. Built on the proven P320 platform, this optic-ready slide pairs a factory-installed ROMEO-X PRO reflex sight with XRay3 day/night iron sights—giving you a low-mounted optic that doesn't force you into suppressor-height sights when you want to run irons alone. If you're setting up a duty gun, competition rig, or carry pistol that demands both speed and backup precision, this assembly simplifies the build.

The slide is machined from stainless steel and finished in Coyote Nitron, a durable coating that resists corrosion and wear. It's engineered to work with Compact-size grip modules—both X-Series and non-X-Series frames—so you can configure the gun to your hand and your mission. The optic-ready design uses the PRO (DeltaPoint Pro) footprint, and the slide accepts standard 9mm Luger barrels (sold separately). One critical detail: this assembly is compatible only with 9mm, .357 SIG, and .40 S&W fire control units; it will not function with a .45 ACP FCU.

Whether you're building a bedside defensive pistol, a range gun, or a competition shooter, the P320 Pro eliminates guesswork. You get a proven optic mounted low and solid, factory-quality construction, and the flexibility to use either the reflex sight or your irons depending on the shot or the situation. The 3.9-inch barrel length gives you a compact-sized platform that's easy to deploy, and the Coyote finish blends professional function with modern aesthetics.

Key Features

• Factory-installed ROMEO-X PRO reflex sight mounted low on the slide
• XRay3 day/night iron sights for intuitive sight picture with or without the optic
• Compatible with Compact-size grip modules (X-Series and standard P320 frames)
• Stainless steel construction with durable Coyote Nitron finish
• Optic-ready PRO (DeltaPoint Pro) footprint for future sight compatibility
• 3.9-inch barrel length for balanced concealability and control
• Accepts standard 9mm Luger barrels

Specifications

Frequently Asked Questions

What grip modules does this slide fit?

The P320 Pro slide is designed for Compact-size grip modules, including both Sig's X-Series and standard (non-X-Series) Compact frames. It will not fit Full-size or Subcompact modules.

Do I have to use the reflex sight, or can I run it with just iron sights?

You have both options. The ROMEO-X PRO is factory-installed and sits low on the slide, so you can use the XRay3 iron sights alone if you prefer. The low optic mount allows standard-height iron sights to coexist, giving you flexibility in how you aim.

What fire control units (FCU) will work with this slide?

This slide is compatible with 9mm Luger, .357 SIG, and .40 S&W fire control units. It will not function with a .45 ACP FCU, so confirm your FCU caliber before assembly.

Does the barrel come with this slide assembly?

No, the barrel is not included. You will need to source a compatible 9mm barrel separately and fit it to the slide during assembly.