Hi Leonard and welcome. To mount a Sig Sauer Romeo1 Pro (which uses the larger DeltaPoint Pro footprint) on this slide, you need an adapter plate that converts an RMSc cut to a DeltaPoint Pro/Romeo1 Pro footprint. Adapter Plate here: sastacticalcustoms.com/products/rms-to-dppro-adapter-red-dot-adapter-plate?srsltid=AfmBOooFp9ndoVBYv7rmIPzHs9O2XT0S8-AdULlrP2WvepI0vjICgm0v -------------------------------- Select the 0.225" cut depth option (suitable for Tisas 1911). Because you are adapting a small cut (RMSc) to a large optic (Romeo1 Pro), the optic will sit high, and you will not be able to co-witness standard-height iron sights.Hardware: Ensure you use the correct screws supplied with the adapter plate. The Tisas slide is typically threaded for M3 screws.Thread Locker: Apply blue Loctite to mounting screws. Cheers and stay safe!

The TISAS Night Stalker 1911 Pro (both single and double-stack models) comes from the factory with an optic-ready cut specifically for the Shield RMSc/Holosun K-Series footprint.
Because the Sig Romeo1 Pro uses a much larger, proprietary footprint (similar to a DeltaPoint Pro) and not the RMSc/K-series footprint, you cannot mount it directly, and a simple adapter plate might create a very high, unstable setup.
Here are the best options for mounting your Romeo1 Pro:
1. Recommended Approach: Use a Different Optic
The most stable and recommended approach for the Tisas Night Stalker is to use an optic that matches the RMSc/Holosun K footprint, such as the Holosun 407K/507K, EPS Carry, or Shield RMSc.
2. Adapter Option (If you must use Romeo1 Pro)
If you are set on using the Romeo1 Pro, you need an adapter that converts an RMSc cut to a Romeo1 Pro/DPP footprint.
SAS Tactical Customs offers specialized adapters for Tisas 1911s. You should look for an "RMS-to-DPPro Adapter".
Note: Because the Romeo1 Pro is much wider than the slide of the Night Stalker, it will have significant overhang on both sides.
Key Details for Installation
Screw Size: Tisas slides generally use M3 screws for their optic cuts.
Recoil Bosses: The Romeo1 Pro does not have the same recoil boss slots as a true DeltaPoint Pro, so ensure the adapter plate you choose accounts for this. Hope this helps. Have a good rest of your day.
🇺🇸🇺🇸 'Merica' 🇺🇸🇺🇸

The Tisas Night Stalker 1911 (Pro/SF/DS models) features an optics-ready slide with a factory cut for the Shield RMSc/Holosun 507K footprint.
Because the Romeo1 Pro uses a larger footprint similar to the DeltaPoint Pro (DPP) or a proprietary SIG footprint, it cannot be mounted directly to the Night Stalker's RMSc/507K cut. You need an adapter plate to convert the RMSc cut to the Romeo1 Pro.
Recommended Adapter Plate
You will need a specific "RMSc to Romeo1 Pro" adapter.
Best Option: The SAS Tactical Customs RMS-to-DPPro Adapter Plate is designed to fit the Tisas cut (RMSc) and allow the mounting of a Romeo1 Pro (which shares a similar footprint to the DPP mentioned in their documentation).
Important Step: When ordering from SAS Tactical Customs, specify your cut (RMSc) and the optic (Romeo1 Pro). The Tisas slide is generally cut for M3 screws.
Another option for converting RMSc/Holosun K cuts to larger footprints is C&H Precision, though they are often specialized in RMR or Holosun-K patterns.