Romeo M17: SIG Red Dot Sight With NSN for the M17/P320 Series

October 25, 2023  
Categories: Guns

The SIG Romeo M17 is a red dot sight (RDS) from SIG Electro-Optics, designed specifically for the M17/M18 handguns that replaced the US military’s Beretta M9 in 2017. It was first revealed by SIG SAUER at SHOT Show 2023 and subsequently received a National Stock Number (NSN) in October.

Romeo 17 SIG red dot sight for M17 and M18 pistols.

The RM17 is a coyote tan, enclosed optic with a 2 MOA reticle, 32 MOA circle, and no (i.e. 1x) magnification. Sight adjustment increments are 1.5 MOA and it features 12 daylight and 3 nightvision illumination settings. Power is provided by a single CR2032 battery. 

Romeo M17 for Sale

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Romeo M17

SIG’s military-issue red dot is a fully enclosed, gas-purged red dot reflex sight with a glass aspheric lens. Likely more important to sharp-end users, it features a flexure-arm adjustment system. The flexure arm is made of beryllium copper and is used in place of springs − this increases durability and also lowers the optic’s deck for better co-witness with regular pistol sights. 

Ten things to know about the SIG Romeo-M17 red dot sight reflex optic. 

1. It utilizes independent brightness adjustment buttons

2. Adjustment buttons are recessed within a protective plate and can be manipulated with gloves on

3. The battery is side-mounted with a threaded battery cap so you can swap batteries without removing the optic

4. Mounting to the handgun is done with the SIG-LOC mounting system

The ROMEO M17 red dot sight mounts to the pistol slide using the SIG-LOC system.

5. Mounting is done from beneath the pistol slide, utilizing the rear sight block and sight block screw.

6. The optic uses MAGNETAC, which turns it off when the weapon is holstered. 

7. It utilizes MOTAC to complement MAGNETAC. MOTAC is SIG’s motion-sensing technology 

ROMEO M17 red dot sight: designed from the ground up for military use.

Recognizing the many advantages of a pistol red dot, the U.S. Army sought an optic for its issued handguns; to that end, a wide array of red dot sights from multiple manufacturers were evaluated. Testing for performance and durability was conducted under a variety of arduous conditions, particularly environmental ones. The Romeo-M17 was the Army’s final choice.

8. It features D.A.R.C. lens technology for use with night vision devices 

9. Run time is advised to be 20k hours at a medium brightness setting.

10. There are two drain holes machined in the housing; this allows liquid to escape when the pistol goes from vertical (i.e. holstered) to horizontal (i.e. extended after the draw)

MAGNETAC: Learn more

MAGNETAC, or Magnetic Activation, is a sensor system in the optic. That sensor detects a Neodymium magnet inside a compatible holster, automatically turning the optic off when holstered (thus conserving battery life). When the weapon is drawn that connection is severed. The optic powers on instantly, immediately going to the last setting used.

MOTAC: Learn More

Activated through motion-sensing technology, MOTAC activates the optic via motion sensing technology. It immediately powers up illumination when triggered by movement and powers down when it does not. This extends battery life.

D.A.R.C. Tech: Learn more

D.A.R.C. stands for “Dark Adaptive Reticles and Coatings.” It represents the complementary efforts of specialized lens coatings and reticle brightness settings to optimize use with Gen 3+ night vision devices.

Among the most important of the M17 red dot’s various features to note before you go out and buy one is #4 from above: the use of the SIG-LOC mounting information. This is significant because of interface and fitment. 

The ROMEO-M17 pistol optic will only fit M17/M18 military issue and SIG commemorative/special-edition pistols with a single optics plate mounting screw.

It might fit other pistols, but SIG “officially” advises there is no compatibility with other pistols. 

SIG-LOC: Learn more

SIG-LOC is the SIG SAUER Leverage Optimizing Connection. It’s a proprietary mounting surface intended to be the “ultimate optic/pistol lockup.” Unlike the vast majority of top-of-slide mounted optics, SIG-LOC attaches the red dot to the slide from below.

SIG-LOC mounting for the M17 red dot

ROMEO-M17 Specs

  • Objective Lens Diameter: 24mm
  • Reticle: Circle dot with 2 MOA Red Dot / 32 MOA Circle
  • Lens Type: Asphere
  • Brightness Adjustment Settings: 15 (12 Day / 3 Night Vision)
  • Water Resistance: Submersible to 20 meters
  • Overall Length: 2.4 inches
  • Overall Width: 0.9 inches
  • Overall Height: 1.1 inches
  • Mounting Footprint: SIG-LOC MHS
  • Battery Type: CR2032
  • Battery Location: Side
  • Weight (w/o battery): 1.5 ounces


Romeo M17 demonstration, drawing from Safariland M17 holster.

Drawing a service weapon from an issued holster: Safariland provides dedicated M17 holster options to the military and associated organizations. The acquisition of an NSN (which can also mean NATO stock number) is not a surprise, given that the RDS was specifically designed “from the ground up” for the M17 and M18. Those weapons, a “military” version of the SIG P320 and SIG P320C pistols respectively, were the final selection of the Modular Handgun System (MHS program, q.v.). Note: Safariland also provides an M18 holster for the compact version. 


ROMEO M17 red dot sight cycling during demonstrations similar to tests conducted during the Modular Handgun System program Additional Authorized List (AAL).

The M17 pistol is based on the SIG P320; the M18 pistol, a smaller version, is based on the SIG P320C Compact.


Additional reading


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EDITOR SIG Romeo M17 red dot



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Mad Duo

Mad Duo

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1 Comment

  1. Doug

    Man, I sure hope prices come down as production ramps up. $800 is steep for a pistol dot!


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