Optics ready plates for Sig models

Sig Sauer offers a wide range of factory optics-ready pistols – from modular P320 variants through compact P365 models to classic P-series like P226 Legion RX. Each of these uses its own combination of slide cut, screw pattern and rear sight layout, so choosing the correct adapter plate is essential.

This category gathers optic plates for factory optics-ready Sig models. Here you’ll find adapter plates that match your specific slide cut and chosen red dot footprint – whether your pistol keeps the rear sight in a separate dovetail or loses it together with the cover plate.

Sig optics-ready families at a glance

Among the most common optics-ready Sig pistols you’ll find:

• Sig P320 family: RX / RXP, X-Series, Pro Cut slides, M17/M18, Legion and other P320 variants.
• Sig P365 family: P365, P365X, P365XL, P365-380, P365 Macro and related models with micro red-dot cuts.
• Classic P-Series: optics-ready versions of P226, P229 and other models (often Legion or RX variants with dedicated cuts for micro red dots).

Even within one family (especially P320), slide cuts are not universal. Always check both your exact model name and how the rear sight is mounted before choosing a plate.

Understand your P320 optics cut & rear sight layout

Because P320 has so many versions, it’s worth knowing how your slide is configured – especially how the rear sight relates to the optics cut:

• Rear sight behind the optics cut: On some P320 optics-ready slides, the rear sight sits in its own dovetail behind the optic cut. When you remove the cover plate, the rear sight stays in place and you can use a low-profile plate for your red dot.
  • You may encounter names such as “Pro Cut” or “Pro Cut with RMR holes” for these models. In practice, both Pro Cut and Pro Cut with RMR holes use the same adapter plates, because the plate attaches to the original DeltaPoint Pro–style cut. The extra RMR holes are there only for direct mounting attempts (not recommended, as all recoil would be transferred into two screws instead of being absorbed by plate borders and pins).
  • You can find all matching adapters here:
    • Optics Ready plates for Sig P320 with Pro Cut
    • Optics Ready plates for Sig P320 with Pro Cut and RMR holes
  • These adapter plates also work with P320 models that have the rear sight integrated in the cover plate (it does not work vice versa, though).
• Rear sight integrated in the cover plate: Other P320 models (including many M17/M18, Legion and RXP-style slides) use a cover plate that combines the optic cover and rear sight. When you remove this plate to mount a red dot, the rear sight disappears – in that case, you may prefer a plate with an integrated rear sight or a plate that adds a new rear dovetail. All compatible plates for P320 models that lose the rear sight when you remove the optics-ready cover are listed here: Optics ready plates for Sig P320 models with removable rear sight.
• Older P320 optics cuts: Some earlier P320 models (for example older P320 X-FIVE from around 2014–2018) use an older optic cut, which you can recognise by its straight “flat” ending in the slide cut. For these you’ll find matching plates here: Optics ready plates for Sig P320-XFIVE.

P365-family optics cuts

Most optics-ready P365 slides come with a micro red-dot cut designed around Shield RMSc / Holosun K-series style footprints. Many dots in this category can be installed directly without a plate, but adapter plates are useful if you:

• want to swap to a different footprint (for example RMR or Noblex/Venom type), or
• need a plate that adds or raises a rear sight for co-witness with your optic.

Plates for P365 models are specific to the P365 slide – they are not interchangeable with P320 plates or with classic P-series plates.

Optics-ready classic P-series (P226, P229, etc.)

Optics-ready versions of classic P-series pistols – such as P226 Legion RX or P229 Legion RX – typically feature a dedicated factory cut tailored to micro red dots like Romeo1 Pro / DPP-type optics. For these models you’ll also find plates that:

• adapt the factory cut to other popular footprints, and
• keep or reintroduce a usable rear sight when the cover plate is removed.

Plates available for major red dot footprints

Our adapter plates cover a wide range of popular red dot mounting patterns, including (model-dependent):

• Trijicon RMR / SRO
• Leupold DeltaPoint Pro / Romeo1Pro-type cuts
• Shield RMSc
• Holosun K-Series
• Noblex / Vortex Venom
• Aimpoint Acro
• C-More RTS

Always check the individual product description for the exact combination of Sig slide type + optic footprint it supports (for example: P320 RX, X-Five non-Legion, X-Five Legion, XCarry, XFull R2, M17/M18, P365X, P365XL, P226 Legion RX, etc.).

Precision fit for Sig optics-ready models

Each plate in this collection is CNC-machined specifically for Sig optics-ready slide families. You’ll find:

• Low-profile plates that sit as close to the slide as possible for a lower bore-axis feel.
• Plates with integrated rear sights or rear-dovetail solutions for slides that lose their iron sight when the cover plate is removed.
• Competition-focused plates that maximise window exposure and speed of target acquisition.

This lets you tune your Sig setup – whether P320, P365 or P-series – for carry, duty or competition while keeping a secure mount and reliable zero retention.

Have a non-OR Sig pistol?

If your Sig pistol is not optics-ready from the factory, you can still mount a red dot using dovetail or dedicated mounting solutions. For P320 in particular, explore our red dot mounts for non-OR Sig P320 pistols here.

Not sure which plate fits?

If you’re unsure which Sig slide cut you have or which plate matches your optic, just contact us. Share your exact model name (and ideally a photo of the slide cut), and we’ll help you pick the right adapter plate for your setup.