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What pistols fit the SIG Sauer ROMEO2?

Page last updated . Data compiled September 2026 by Andrew Terrebonne.

It uses the SIG Romeo2 footprint and mounts to 30 of the 178 slides tracked here, 10 of them with no adapter plate. An enclosed-emitter optic: 1.58 oz without shroud, a CR1632 battery, with a 3 / 6 MOA reticle.

No plate neededPlate neededDoesn’t fit

Pistols that fit30 of 178
No plate to buy18
Plate to buy12
FootprintSIG Romeo2
EmitterEnclosed
Window30 mm clear aperture (no width × height published)
Dot options3 / 6 MOA
Weight1.58 oz without shroud
BatteryCR1632
Screws (footprint)M4 × 0.7
Torque (footprint)28 in-lb
Street price$450–650 · SIG Sauer ↗

No plate to buy counts the direct mounts plus the pairings whose plate normally comes in the pistol's or the optic's box. Box contents change between production runs, so check yours before counting on it.

Lens and weight from SIG Sauer, ROMEO2 manual ↗. Checked against them September 26, 2026.

About this opticMounts directly on SIG PRO-cut slides. Other pistols need a ROMEO2 adapter plate, sold separately (SIG ROMEO2 manual).
Sight co-witness, where no sight maker publishes heightsDepends on your front sight height, which can vary by SKU and production run within one model. Standard-height irons: no co-witness. Suppressor-height irons: low in the window at best, since enclosed emitters sit tall. Mounted directly, the optic sits as low as the cut allows, but an enclosed housing gives most of that height back. That's the typical case for this kind of optic, not a guarantee: pistols don't standardize sight and optic heights the way rifles do. Where one does, its figures are below and take precedence.
Sight heights published for this optic on 6 slides
GLOCK 19 Gen5 MOS
  • Night Fision · lower 1/3 · front .330 / rear .353 in
GLOCK 17 Gen5 MOS
  • Night Fision · lower 1/3 · front .330 / rear .353 in
GLOCK 45 Gen5 MOS
  • Night Fision · lower 1/3 · front .330 / rear .353 in
GLOCK 34 Gen5 MOS
  • Night Fision · lower 1/3 · front .330 / rear .353 in
GLOCK 26 Gen5 MOS
  • Night Fision · lower 1/3 · front .330 / rear .353 in
GLOCK 17 / 19 / 34 Gen4 MOS
  • Night Fision · lower 1/3 · front .330 / rear .353 in

Heights are front / rear in inches, as each sight maker measures its own sights. That's not a deck height, and it doesn't compare across makers to the thousandth. Absolute puts the front sight level with the dot; lower 1/3 and lower 1/5 sit it lower in the window. A sight maker sells a handful of fixed heights, so optics of similar height share one set: the same figures under two optics are the maker's chart saying so, not a copy.

Night Fision — co-witness chart for GLOCK 17/19/26/34/45 ↗

SIG Romeo2 footprintSIG's ROMEO2 manual says it mounts directly on SIG PRO-cut slides and on other pistols through adapter plates, which are sold separately.
GuidesSuppressor-height sights: will your irons co-witness? · Installing a red dot: what the makers say · Zeroing a red dot for the first time · Red dot lost zero? Troubleshooting the mount

Simplest slides to mount it on

No plate needed$450–650SIG Sauer P320 X-Carrydirect — no adapter9 other slides also take it with no plateBuild sheet
Plate already in the box$450–650Smith & Wesson M&P9 M2.0 Optics Ready (4.25 / 4.6 / 5 in)in-box plate: C.O.R.E. Plate 6 (DPP family)All 18 with no plate to buyBuild sheet
Cheapest plate to buy$475–710GLOCK 19 Gen5 MOSplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)Every slide it fits, cheapest firstBuild sheet

Cost to mount is the optic plus the cheapest plate that fits, in approximate street-price bands from September 2026, for comparing routes. Pistols aren't priced, so when slides tie, the card names the most popular one.

Every pistol, and how it mounts

ItemSlide cutHow it mountsCost to mount
Direct (cross-fit) — 10
SIG Sauer P320 AXG Legion / AXG ProBuild sheetSIG P320 optic cut (Romeo1Pro pattern)direct — no adapter$450–650
SIG Sauer P320 Spectre CompBuild sheetSIG P320 optic cut (Romeo1Pro pattern)direct — no adapter$450–650
SIG Sauer P320 X-CarryBuild sheetSIG P320 optic cut (Romeo1Pro pattern)direct — no adapter$450–650
SIG Sauer P320 XCompactBuild sheetSIG P320 optic cut (Romeo1Pro pattern)direct — no adapter$450–650
SIG Sauer P320 XFive LegionBuild sheetSIG P320 optic cut (Romeo1Pro pattern)direct — no adapter$450–650
SIG Sauer P320 XTenBuild sheetSIG P320 optic cut (Romeo1Pro pattern)direct — no adapter$450–650
SIG Sauer P320-M17 / M18Build sheetSIG P320 optic cut (Romeo1Pro pattern)direct — no adapter$450–650
Springfield Armory EchelonBuild sheetSpringfield Echelon VISdirect — no adapter$450–650
Springfield Armory Echelon 4.0CBuild sheetSpringfield Echelon VISdirect — no adapter$450–650
Springfield Armory Echelon Compact 4.5CBuild sheetSpringfield Echelon VISdirect — no adapter$450–650
Plate in the box — 8
Smith & Wesson M&P Carry CompBuild sheetS&W M&P C.O.R.E. / Optics Readyin-box plate: C.O.R.E. Plate 6 (DPP family)$450–650
Smith & Wesson M&P CompetitorBuild sheetS&W M&P C.O.R.E. / Optics Readyin-box plate: C.O.R.E. Plate 6 (DPP family)$450–650
Smith & Wesson M&P10mm M2.0 Optics ReadyBuild sheetS&W M&P C.O.R.E. / Optics Readyin-box plate: C.O.R.E. Plate 6 (DPP family)$450–650
Smith & Wesson M&P9 C.O.R.E. (pre-M2.0)Build sheetS&W M&P C.O.R.E. / Optics Readyin-box plate: C.O.R.E. Plate 6 (DPP family)$450–650
Smith & Wesson M&P9 M2.0 Compact Optics ReadyBuild sheetS&W M&P C.O.R.E. / Optics Readyin-box plate: C.O.R.E. Plate 6 (DPP family)$450–650
Smith & Wesson M&P9 M2.0 MetalBuild sheetS&W M&P C.O.R.E. / Optics Readyin-box plate: C.O.R.E. Plate 6 (DPP family)$450–650
Smith & Wesson M&P9 M2.0 Optics Ready (4.25 / 4.6 / 5 in)Build sheetS&W M&P C.O.R.E. / Optics Readyin-box plate: C.O.R.E. Plate 6 (DPP family)$450–650
Smith & Wesson Performance Center M&P9 M2.0 Metal / Spec SeriesBuild sheetS&W M&P C.O.R.E. / Optics Readyin-box plate: C.O.R.E. Plate 6 (DPP family)$450–650
Plate to buy — 12
GLOCK 17 / 19 / 34 Gen4 MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 17 Gen5 MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 19 Gen5 MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 19X MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 22 / 23 Gen5 MOS (.40)Build sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 26 Gen5 MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 34 Gen5 MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 35 Gen5 MOS (.40)Build sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 44 MOS (.22 LR)Build sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 45 Gen5 MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 47 Gen5 MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
GLOCK 49 Gen5 MOSBuild sheetGLOCK MOS — standard & full sizeplate: ROMEO2 GLOCK MOS adapter plate (SOR2M102)$475–710
No fit — 148
1911 / 2011 Non-optics-ready slideNo factory optic provisionno known route—
Any pistol No factory optic cut — custom mill requiredNo factory optic provisionno known route—
Archon Firearms Type B / Type D ORRMSc-pattern direct cutno known route—
Arex Delta Gen.2Arex Delta Gen.2 plate systemno known route—
Arex Zero 1 TacticalArex Zero 1 Tactical ROR plate systemno known route—
Avidity Arms PD10RMSc-pattern direct cutno known route—
Beretta 80X CheetahBeretta 80X Cheetah plate systemno known route—
Beretta 92 GTSBeretta 92X / M9A4 plate systemno known route—
Beretta 92FS / M9 (no optic cut)No factory optic provisionno known route—
Beretta 92FS X Performance ORBeretta 92X / M9A4 plate systemno known route—
Beretta 92X / 92XI / 92XI SAOBeretta 92X / M9A4 plate systemno known route—
Beretta 92X RDOBeretta 92X / M9A4 plate systemno known route—
Beretta 92XI SqualoBeretta 92X / M9A4 plate systemno known route—
Beretta 94X PerformanceBeretta 92X / M9A4 plate systemno known route—
Beretta APX A1 CarryRMSc-pattern direct cutno known route—
Beretta APX A1 CompactBeretta APX A1 / APX RDO plate systemno known route—
Beretta APX A1 Full SizeBeretta APX A1 / APX RDO plate systemno known route—
Beretta APX RDOBeretta APX A1 / APX RDO plate systemno known route—
Beretta M9A4Beretta 92X / M9A4 plate systemno known route—
Bersa BP9CC ORRMSc-pattern direct cutno known route—
Canik METE MC9 / MC9LRMSc-pattern direct cutno known route—
Canik METE MC9 PrimeRMSc-pattern direct cutno known route—
Canik METE SFCanik METE optic cut (RMSc plus RMRcc or RMR)no known route—
Canik METE SFTCanik METE optic cut (RMSc plus RMRcc or RMR)no known route—
Canik METE SFT ProCanik METE optic cut (RMSc plus RMRcc or RMR)no known route—
Canik METE SFxCanik METE optic cut (RMSc plus RMRcc or RMR)no known route—
Canik SFx Rival / Rival-SCanik SFx Rival optic interface platesno known route—
Canik TP9 Elite SCCanik TP9 Elite SC optic interfaceno known route—
Canik TP9 SFxCanik TP9 SFx optic interface platesno known route—
Canik TTI CombatCanik TTI Combat optic interface platesno known route—
Canik TTI Combat MasterCanik TTI Combat optic interface platesno known route—
CZ 75 / SP-01 / Shadow 2 (non-OR)Rear-sight dovetail mountno known route—
CZ P-07 / P-09 (standard, no optic cut)Rear-sight dovetail mountno known route—
CZ P-07 NocturneCZ Nocturne direct cutno known route—
CZ P-09 Nocturne / P-09C NocturneCZ Nocturne direct cutno known route—
CZ P-10 C Optics ReadyCZ P-10 OR plate systemno known route—
CZ P-10 F Optics ReadyCZ P-10 OR plate systemno known route—
CZ P-10 S Optics ReadyCZ P-10 OR plate systemno known route—
CZ Shadow 2 CarryCZ Shadow 2 Carry direct cut (Shield RMSc and Holosun K)no known route—
CZ Shadow 2 Compact Optics ReadyCZ Shadow 2 OR plate systemno known route—
CZ Shadow 2 Optics ReadyCZ Shadow 2 OR plate systemno known route—
FN 509 CC EdgeFN MRD plate systemno known route—
FN 509 LS EdgeFN MRD plate systemno known route—
FN 509 Midsize MRD / Compact MRDFN MRD plate systemno known route—
FN 509 MRD / TacticalFN MRD plate systemno known route—
FN 510 / 545 MRDFN MRD plate systemno known route—
FN Reflex MRDRMSc-pattern direct cutno known route—
Girsan Witness2311RMSc-pattern direct cutno known route—
GLOCK 17 / 19 (non-MOS, no optic cut)No factory optic provisionno known route—
GLOCK 17 / 19 / 45 Gen6 (ORS)GLOCK Gen6 ORSno known route—
GLOCK 17 / 19 / 45 Gen6 A-CutAimpoint A-Cutno known route—
GLOCK 20 Gen5 MOS (10 mm)GLOCK MOS — 10 mm / .45 framesno known route—
GLOCK 21 Gen5 MOS (.45)GLOCK MOS — 10 mm / .45 framesno known route—
GLOCK 40 MOS (10 mm)GLOCK MOS — 10 mm / .45 framesno known route—
GLOCK 41 MOS (.45)GLOCK MOS — 10 mm / .45 framesno known route—
GLOCK 43X / 48 MOS-KGLOCK Slimline MOS-Kno known route—
GLOCK 43X / 48 Rail MOSGLOCK Slimline MOS (43X / 48)no known route—
GLOCK 43X MOSGLOCK Slimline MOS (43X / 48)no known route—
GLOCK 48 MOSGLOCK Slimline MOS (43X / 48)no known route—
Heckler & Koch SFP9 OR (European VP9)HK VP9 / SFP9 OR plate systemno known route—
Heckler & Koch VP9 Match ORHK VP9 / SFP9 OR plate systemno known route—
Heckler & Koch VP9 Optics ReadyHK VP9 / SFP9 OR plate systemno known route—
Heckler & Koch VP9SK Optics ReadyHK VP9 / SFP9 OR plate systemno known route—
IWI Masada SlimRMSc-pattern direct cutno known route—
Kimber KDS9cKimber KDS9c plate systemno known route—
Kimber R7 MakoKimber R7 Mako plate systemno known route—
Mossberg MC2sc Optic ReadyRMSc-pattern direct cutno known route—
Palmetto State Armory 5.7 Rock Optics ReadyRMSc-pattern direct cutno known route—
Palmetto State Armory Dagger Full Size / Compact (RMR cut)PSA Dagger RMR cutno known route—
Palmetto State Armory Dagger MicroRMSc-pattern direct cutno known route—
Rock Island Armory STK100RMSc-pattern direct cutno known route—
Rost Martin RM1CRost Martin metal optic plate systemno known route—
Rost Martin RM1SPlate system — fitment not publishedno known route—
Ruger American Pistol CompetitionPlate system — fitment not publishedno known route—
Ruger MAX-9RMSc-pattern direct cutno known route—
Ruger Ruger-5.7 Optics ReadyRMSc-pattern direct cutno known route—
Ruger RXMRuger RXM direct-mount optic cut (RMR, DPP, RMSc)no known route—
Ruger RXM CompactRuger RXM direct-mount optic cut (RMR, DPP, RMSc)no known route—
SCCY CPX RDR / DVG-1 RDRRMSc-pattern direct cutno known route—
Shadow Systems CR920 / CR920PShadow Systems CR920 optic cut (RMSc pattern)no known route—
Shadow Systems DR920 / DR920PShadow Systems multi-optic cut (MR920, DR920, XR920)no known route—
Shadow Systems Foundation SeriesShadow Systems multi-optic cut (MR920, DR920, XR920)no known route—
Shadow Systems MR920Shadow Systems multi-optic cut (MR920, DR920, XR920)no known route—
Shadow Systems MR920 Elite / CombatShadow Systems multi-optic cut (MR920, DR920, XR920)no known route—
Shadow Systems XR920 / XR920PShadow Systems multi-optic cut (MR920, DR920, XR920)no known route—
SIG Sauer P226 / P229 (non-RX, no optic cut)No factory optic provisionno known route—
SIG Sauer P226 / P229 Legion RXSIG Romeo1 cut (P226 / P229 RX Legion)no known route—
SIG Sauer P320 Full-Size / Carry (SIG-LOC PRO slide)SIG-LOC PRO slide — P320no known route—
SIG Sauer P320-M17 / M18 (SIG-LOC slide)SIG-LOC slide — M17 / M18no known route—
SIG Sauer P322 / P322 CompSIG P322 optic cut (RMSc pattern)no known route—
SIG Sauer P365 FuseSIG P365 optic cut (RMSc pattern)no known route—
SIG Sauer P365 Optics ReadySIG P365 optic cut (RMSc pattern)no known route—
SIG Sauer P365-380SIG P365 optic cut (RMSc pattern)no known route—
SIG Sauer P365-AXG LegionSIG P365 optic cut (RMSc pattern)no known route—
SIG Sauer P365-XMACRO / XMACRO CompSIG P365 optic cut (RMSc pattern)no known route—
SIG Sauer P365XSIG P365 optic cut (RMSc pattern)no known route—
SIG Sauer P365X / P365-XL / P365-AXG Legion (SIG-LOC slide)SIG-LOC slide — P365no known route—
SIG Sauer P365XLSIG P365 optic cut (RMSc pattern)no known route—
Smith & Wesson CSX E-Series Optics ReadyRMSc-pattern direct cutno known route—
Smith & Wesson M&P 22 MagnumRMSc-pattern direct cutno known route—
Smith & Wesson M&P 5.7S&W M&P 5.7 direct cutno known route—
Smith & Wesson M&P EqualizerS&W Equalizer optic cutno known route—
Smith & Wesson M&P Shield M2.0 Optics ReadyS&W M&P Shield M2.0 optics-ready cutno known route—
Smith & Wesson M&P Shield Plus Carry CompRMSc-pattern direct cutno known route—
Smith & Wesson M&P Shield Plus Optics ReadyS&W M&P Shield Plus optics-ready cutno known route—
Smith & Wesson M&P9 M2.0 (non-OR, no optic cut)No factory optic provisionno known route—
Smith & Wesson M&P9 M2.0 Metal with Aimpoint ACRO CutS&W M&P ACRO direct cutno known route—
Springfield Armory 1911 DS Operator AOSSpringfield AOSno known route—
Springfield Armory 1911 DS Prodigy 4.25in COAAimpoint A-Cutno known route—
Springfield Armory 1911 Operator .45 COAAimpoint A-Cutno known route—
Springfield Armory 1911 TRP .45 COAAimpoint A-Cutno known route—
Springfield Armory Echelon 4.0C COAAimpoint A-Cutno known route—
Springfield Armory Echelon 4.0FC COAAimpoint A-Cutno known route—
Springfield Armory Echelon 4.5F COAAimpoint A-Cutno known route—
Springfield Armory Hellcat OSPSpringfield Hellcat OSP cut (Micro footprint)no known route—
Springfield Armory Hellcat ProSpringfield Hellcat OSP cut (Micro footprint)no known route—
Springfield Armory Hellcat Pro Comp OSPSpringfield Hellcat OSP cut (Micro footprint)no known route—
Springfield Armory Hellcat RDPSpringfield Hellcat OSP cut (Micro footprint)no known route—
Springfield Armory Prodigy (1911 DS)Springfield AOSno known route—
Springfield Armory XD-M Elite OSPSpringfield AOSno known route—
Springfield Armory XD-S Mod.2 OSPRMSc-pattern direct cutno known route—
Staccato C2Staccato / 2011 optic plate systemno known route—
Staccato CSRMSc-pattern direct cutno known route—
Staccato PStaccato / 2011 optic plate systemno known route—
Staccato XCStaccato / 2011 optic plate systemno known route—
Staccato XLStaccato / 2011 optic plate systemno known route—
Stoeger STR-9MCRMSc-pattern direct cutno known route—
Taurus Defender 856 TOROTaurus 856 T.O.R.O. revolver cutno known route—
Taurus G3 TORO / G3X TOROTaurus T.O.R.O. plate systemno known route—
Taurus G3C TORO / G3X TOROTaurus T.O.R.O. plate systemno known route—
Taurus GX4 Carry TOROTaurus GX4 T.O.R.O. direct cutno known route—
Taurus GX4 Graphene TOROTaurus GX4 T.O.R.O. direct cutno known route—
Taurus GX4 TORO / GX4XLTaurus GX4 T.O.R.O. direct cutno known route—
Taurus Judge TORO / Raging HunterTaurus Judge T.O.R.O. revolver cutno known route—
Taurus TX22 CompactRMSc-pattern direct cutno known route—
Tisas Carry DS / Duty DSRMSc-pattern direct cutno known route—
Walther PDP 2.0 CompactWalther PDP 2.0 optic cutno known route—
Walther PDP 2.0 Full SizeWalther PDP 2.0 optic cutno known route—
Walther PDP Compact (1.0)Walther PDP 1.0 optic cutno known route—
Walther PDP Compact F-SeriesWalther PDP 1.0 optic cutno known route—
Walther PDP F-SeriesWalther PDP 1.0 optic cutno known route—
Walther PDP Full Size (1.0)Walther PDP 1.0 optic cutno known route—
Walther PDP ProWalther PDP 1.0 optic cutno known route—
Walther PDP Pro SDWalther PDP 1.0 optic cutno known route—
Walther PDP Steel FrameWalther PDP 1.0 optic cutno known route—
Walther Q4 SF Optics ReadyWalther Q4 SF / Q5 Match SF optic cutno known route—
Walther Q5 Match SFWalther Q4 SF / Q5 Match SF optic cutno known route—
Walther WMPPlate system — fitment not publishedno known route—

Already own it?

Taking it from one pistol to another? What changes on each kind of slide: the plate, the screw thread at each joint, torque and thread traps.

Build one

Open the fit checker with this optic selected, or click any "how it mounts" cell above for that pairing's verdict and build sheet.

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