Red dot sights
Sig Sauer Romeo5 Gen II: Full Specifications
Quick answer
The SIG SAUER ROMEO5 GEN II 1x20 Red Dot Sight lists at $128.98. Published figures: magnification 1x, objective lens 20 mm, dot size 2 MOA. It suits a rifle that is stored ready and grabbed without warning.
Motion activation is the feature that matters: the sight switches itself off when the rifle sits still and wakes instantly when it moves, so the battery lasts years left on.
Every figure below is the manufacturer's own published specification, taken from the product listing and the data sheet. Where a figure is not published it is left out rather than estimated, which is why some sheets are shorter than others. Price is the listed price when this page was last compiled and it changes often.
On this page
Sig Sauer Romeo5 Gen II specifications
The Sig Sauer Romeo5 Gen II publishes magnification 1x, objective lens 20 mm, dot size 2 MOA, at a listed price of $128.98.
Sourced figure
| Specification | Published figure |
|---|---|
| Magnification | 1x |
| Objective lens | 20 mm |
| Dot size | 2 MOA |
| Motion activation | Yes |
Specifications above are the manufacturer published figures, taken from the product listing. Figures the maker does not publish, such as total elevation travel or exact eye relief, are omitted here rather than estimated.
What the manufacturer says about it
The manufacturer own listing bullets, quoted rather than paraphrased so you can judge the claims yourself. These are marketing copy, not independent measurement.
Sig Sauer lists 5 headline points for the Romeo5 Gen II, quoted here verbatim.
| Manufacturer listing point |
|---|
| ROMEO5 GEN II - The ROMEO5 GEN II red dot sight represents the next step in the evolution of SIG SAUER's best-selling Electro-Optics series, now refreshed with a bold new design & enhanced functionality; This high-performance 1x aiming sight is designed to meet the rigorous demands of civilians and armed professionals alike |
| NEXT-GEN PERFORMANCE - This compact red dot sight features ambidextrous top-mounted illumination controls, allowing users to easily adjust brightness levels for any situation; Featuring 10 daylight and 2 NV settings, this red dot sight ensures you have the perfect level of illumination for precise targeting in diverse environments |
| UNMATCHED CLARITY - Engineered with a fully multi-coated lens that enhances light transmission, this red dot sight delivers clear sight pictures even in challenging lighting conditions; Thanks to the parallax-free optical design, the point of aim remains consistent regardless of eye position, providing unparalleled accuracy and confidence in every shot |
| DURABLE CONSTRUCTION - Built to withstand harsh conditions, the optic's IPX7 rating offers dependable waterproof and fog-proof performance, ensuring reliability in any weather or situation; The rugged industrial design is further enhanced by a new I-BEAM mount that maximizes situational awareness, delivering a stable and secure platform for your red dot sight |
| INCREASED BATTERY LIFE - The ROMEO5 GEN II shooting sight provides a 1x enclosed aiming solution for today's carbine platforms, with a crisp 2 MOA red dot emitter powered by a single battery that can be quickly replaced; Coupled with SIG SAUER'S motion-activated MOTAC technology, this dot sight boasts an industry-leading 40,000-hour runtime under normal use; MOTAC immediately powers up illumination when it senses motion and powers down when it does not in order to extend battery life |
What this optic suits
Best for: a rifle that is stored ready and grabbed without warning.
Category: red dot sights. The honest test for any optic is whether its numbers match your rifle and the distances you actually shoot rather than whether it is a good product in the abstract. Work out what ring height you need, what exit pupil the magnification gives you and how much elevation the distance demands, using the calculators on this site, then check this model against those answers.
The closest alternatives at a similar price
Same category, nearest price. An alternative with no stated reason is filler, so each of these is here because it trades something specific against the model above.
Vortex Crossfire Red Dot Sight Gen II, 2 MOA Red Dot
$119.99A tube style sight rather than an open reflex, which keeps rain and snow off the emitter. That is a real advantage in weather and a real disadvantage in weight.
Best for: a red dot used in genuinely bad weather
Check price on Amazon
Holosun ARO-CORE Red Dot Sight with Shake Awake, 22mm Window
$119.99Holosun built its reputation on battery life and shake awake, and the larger 22 mm window makes finding the dot much faster than a small tube sight.
Best for: fast target acquisition with a wide field of view
Check price on Amazon
Bushnell TRS-25 HiRise 1x25 Red Dot Sight with Riser
$107.69The entry point that has been on more rifles than any other red dot, and the riser version puts the dot at a usable height on a flat top receiver rather than uselessly low.
Best for: the cheapest red dot from an established maker
Check price on Amazon
Vortex SPARC Red Dot Sight Gen II, 2 MOA Dot
$99.99A 2 MOA dot, a transferable lifetime warranty, and a mount that gives you both an absolute and a lower third height from the same box.
Best for: a first red dot that will not need replacing
Check price on AmazonSide by side
| Model | Price | Magnification | Objective lens | Dot size | Motion activation |
|---|---|---|---|---|---|
 SIG SAUER ROMEO5 GEN II 1x20 Red Dot Sight | $128.98 | 1x | 20 mm | 2 MOA | Yes |
| Vortex Crossfire Red Dot Sight Gen II, 2 MOA Red Dot | $119.99 | 1x | - | 2 MOA | - |
| Holosun ARO-CORE Red Dot Sight with Shake Awake, 22mm Window | $119.99 | 1x | 22 mm | - | Yes |
| Bushnell TRS-25 HiRise 1x25 Red Dot Sight with Riser | $107.69 | 1x | 25 mm | 3 MOA | - |
A dash means the manufacturer does not publish that figure. We leave it blank rather than estimating it.
How we chose
We did not test these optics in person and we never claim to. Picks are researched from manufacturer specification sheets, published optical and ballistic formulas, and the recurring themes in verified owner reviews. Every pick is matched to a real objective diameter, a real tube size, a real ring height or a real exit pupil rather than to a price bracket, and it is placed in the tier where its capability actually belongs. Where a figure is shooter convention rather than a sourced number we label it, and where a manufacturer does not publish a figure we leave it out instead of estimating it.
Sources
- Sig Sauer published specifications for the Romeo5 Gen II
- Amazon product listing features and current pricing
Frequently asked questions
How much does the Sig Sauer Romeo5 Gen II cost?
It was listed at $128.98 when this page was last compiled. Optics pricing moves frequently and promotional pricing is common, so treat that as a planning figure and confirm the current price before committing to a purchase or budgeting a whole setup around it.
Is the Sig Sauer Romeo5 Gen II right for my rifle?
A rifle that is stored ready and grabbed without warning. Beyond that, the honest test is whether it physically fits and whether its numbers match the distances you shoot. Check the ring height its objective needs and the exit pupil its magnification gives before deciding.
Where do these specifications come from?
The manufacturer published figures, taken from the product listing and data sheet. We do not test products in person and we never claim to, so nothing here is a measured result. Where a specification is not published by the manufacturer it is omitted rather than estimated, which is why some sheets are shorter than others.
Will this fit my rifle and my rings?
Check three things in this order. The tube diameter has to match the rings exactly, because a 30 mm ring will not hold a 34 mm tube. The objective bell has to clear the barrel at the ring height you own. And the rail or base pattern on the receiver has to match the mount. Those three account for most returns in this category.
Is it worth buying this rather than the cheaper alternative?
Only if the thing it does better is something you actually need. The alternatives listed above each trade something specific, and on a first setup the money almost always does more good spent on a solid mount, a torque driver and a level than on upgrading the glass by one model.
Researched, not professional advice. This page is compiled from published manufacturer specifications, published optical and ballistic formulas, and owner-review consensus, not hands-on testing. Figures described as a rule of thumb are shooter convention rather than sourced numbers, and they are labelled that way wherever they appear. Ballistic figures come from a point mass model using the ballistic coefficient the maker publishes, so treat them as a starting point and confirm them on paper at a measured distance. Confirm your firearm is unloaded with the action open before you mount, level, torque or bore sight anything. Verify a zero only on a supervised range or a safe, legal backstop, know what lies beyond your target, and follow the law where you hunt and shoot, including rules on land access and permitted cartridges.