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Home / Pistols / SIG Sauer P320-M17 / M18 (SIG-LOC slide)

What red dots fit the SIG Sauer P320-M17 / M18 (SIG-LOC slide)?

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

2 of the 77 optics tracked here mount to this slide, and 2 of those need no adapter plate. This slide uses SIG-LOC slide — M17 / M18.

No plate neededPlate neededDoesn’t fit

Mount systemSIG-LOC slide — M17 / M18
Optics that fit2 of 77
No plate needed2

New to red dots? What footprint, plate, co-witness and the rest mean

Verify this onePublished fitment data for this slide is thin or conflicting. Screws come up from under the slide into the optic. A SIG-LOC slide isn't SIG-LOC-only: SIG says top-mount reflex sights also fit, using removable recoil-lug pins, much like Springfield's VIS pins. SIG doesn't say which footprint those pins recreate, so that route isn't listed here as a fitment. Ask SIG before buying a top-mount optic for this slide. Confirm with the plate maker before ordering.

Cheapest ways to mount it

Cheapest overall, and with no plate$300–450SIG Sauer ROMEO-Xdirect — no adapterBuild sheet
Cheapest enclosed emitter$300–450SIG Sauer ROMEO-Xdirect — no adapterBuild sheet

Every optic, and how it mounts

ItemFootprintHow it mountsCost to mount
Direct — 2
SIG Sauer ROMEO-X EnclosedBuild sheetSIG-LOCdirect — no adapter$300–450
SIG Sauer ROMEO-X SIG-LOC Compact EnclosedBuild sheetSIG-LOCdirect — no adapter$450–650
No fit — 75
ADE Delta ProTrijicon RMRno known route—
ADE NUWAcc ProTrijicon RMRccno known route—
Aimpoint ACRO C-2 EnclosedAimpoint ACROno known route—
Aimpoint ACRO P-1 EnclosedAimpoint ACROno known route—
Aimpoint ACRO P-2 EnclosedAimpoint ACROno known route—
Aimpoint COA EnclosedAimpoint COA / A-Cutno known route—
Aimpoint Micro T-2 EnclosedAimpoint Microno known route—
Ameriglo HavenTrijicon RMRno known route—
Burris FastFire 3Docter / Noblexno known route—
Burris FastFire 4Docter / Noblexno known route—
Bushnell RXS-100Leupold DeltaPoint Prono known route—
C-More RTS2C-More RTS2 / STS2no known route—
C-More STS2C-More RTS2 / STS2no known route—
C&H Precision CompTrijicon RMRno known route—
Crimson Trace CTS-1550Shield RMScno known route—
Cyelee Cat / WolfTrijicon RMRno known route—
EOTECH EFLX MiniLeupold DeltaPoint Prono known route—
Holosun 407C X2Trijicon RMRno known route—
Holosun 407COMPTrijicon RMRno known route—
Holosun 407K X2Holosun Kno known route—
Holosun 507-PromaxTrijicon RMRno known route—
Holosun 507C X2Trijicon RMRno known route—
Holosun 507C X3 / 407C X3Trijicon RMRno known route—
Holosun 507COMPTrijicon RMRno known route—
Holosun 507K X2Holosun Kno known route—
Holosun 507K X3 / 407K X3Holosun Kno known route—
Holosun 508T X2Trijicon RMRno known route—
Holosun 509T EnclosedHolosun 509Tno known route—
Holosun EPS EnclosedHolosun Kno known route—
Holosun EPS Carry EnclosedHolosun Kno known route—
Holosun EPS-CORE EnclosedShield RMScno known route—
Holosun SCS 320 EnclosedHolosun SCS (320)no known route—
Holosun SCS Carry EnclosedHolosun Kno known route—
Holosun SCS MOS EnclosedHolosun SCS (MOS)no known route—
JP Enterprises JPointShield RMScno known route—
Leapers UTG OP3 MicroDocter / Noblexno known route—
Leupold DeltaPoint ProLeupold DeltaPoint Prono known route—
Lucid Optics E7 EnclosedAimpoint ACROno known route—
Meopta MeoSight IVDocter / Noblexno known route—
Meprolight MPO-DFTrijicon RMRno known route—
Noblex Sight III / Docter Sight CDocter / Noblexno known route—
Olight Osight KHolosun Kno known route—
Olight Osight SShield RMScno known route—
Primary Arms Classic 21 mm MicroShield RMScno known route—
Riton 3 TACTIX MPRD 2Shield RMScno known route—
Riton 3 TACTIX PRDTrijicon RMRno known route—
Shield Sights RMS2Shield RMScno known route—
Shield Sights RMScShield RMScno known route—
SIG Sauer ROMEO-X CompactShield RMScno known route—
SIG Sauer ROMEO-X ProLeupold DeltaPoint Prono known route—
SIG Sauer ROMEO-X SIG-LOC Pro EnclosedSIG-LOC PROno known route—
SIG Sauer ROMEO1PROSIG Romeo1Prono known route—
SIG Sauer ROMEO2 EnclosedSIG Romeo2no known route—
SIG Sauer ROMEOZeroShield RMScno known route—
SIG Sauer ROMEOZero EliteShield RMScno known route—
Sightmark Mini Shot A-SpecDocter / Noblexno known route—
Springfield Armory Hex DragonflyDocter / Noblexno known route—
Springfield Armory Hex WaspShield RMScno known route—
Steiner MPS EnclosedAimpoint ACROno known route—
Swampfox Justice IITrijicon RMRno known route—
Swampfox Liberty IITrijicon RMRno known route—
Swampfox Sentinel IIShield RMScno known route—
Trijicon RCR EnclosedTrijicon RCRno known route—
Trijicon RMR HDTrijicon RMRno known route—
Trijicon RMR Type 2Trijicon RMRno known route—
Trijicon RMRccTrijicon RMRccno known route—
Trijicon SROTrijicon RMRno known route—
Viridian RFX35Shield RMScno known route—
Viridian RFX45 EnclosedAimpoint ACROno known route—
Vortex Defender-CCWShield RMScno known route—
Vortex Defender-SLLeupold DeltaPoint Prono known route—
Vortex Defender-STLeupold DeltaPoint Prono known route—
Vortex Defender-XLLeupold DeltaPoint Prono known route—
Vortex VenomDocter / Noblexno known route—
Vortex ViperDocter / Noblexno known route—
GuidesSuppressor-height sights: will your irons co-witness? · Installing a red dot: what the makers say

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