Olight Osight S Review – Now RMSc & Fully Enclosed

The Olight is at it again this year! This is the brand new Olight Osight S, a fully enclosed red dot sight with RMSc footprint this time that some of us have been asking for.

Let's check out how this stack up.

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Olight Osight S Impression

The Olight Osight S follows the same rechargeable design but way smaller to fit the RMSC footprint. The optic itself doesn't have any charging port, and the charging port is on the top of the window.

Olight Osight S Spec

• Footprint: RMSc
• Dot Size: 2 MOA, 32 MOA Ring
• Window Size: 14mm X 21mm
• Dot Colors: Red
• Length: 1.67"
• Width: 1.18"
• Height: 1.48"
• Body: 6061 T6 OAL aluminum
• Design: Closed emitter
• Battery: Rechargeable
• Waterproof: IPX7

The large window size makes the Osight S an affordable option for anyone looking for an enclosed RMSc optic without spending over $400.

Currently EPS Carry, SCS Carry and the Sig ROMEO X Compact are the top 3 enclosed RMSc footprint optics on the market.

While they are expensive, the Osight S enters the market to offer a more price friendly option.

• The question is can it last long without breaking under normal use? 
• Can it be a viable option for concealed carry?
• Does it have hold zero?

Olight Osight S Construction

The Osight S' overall construction is very good. It doesn't feel cheap at all. Olight uses its proprietary aluminum alloy "OAL".

Based on Olight's spec data, it says the following:

• 73% harder than 6061 aluminum
• 19% harder than 7075
• 33% stronger yield strength than 7075
• 24% stronger tensile strength than 7075
• 44% stronger yield strength than TA2 Titanium

It basically matches the strength of Titanium while staying as light as 7075 Aluminum.

For our testing, we are focusing on its range performance first without judging it based on how well it performs if it's dropped on its head. However, we do take that into consideration without completely destroying the optic that isn't realistic.

The Osight S feels pretty beefy like the EPS carry, but the field of view appears much bigger. I can't really pinpoint where, but it just appears wider. Maybe its the thinner lens frame on the side that slightly opens up the field of view. 

This is the side by side view between the EPS and the Osight S:

Deck Height

The overall deck height is extremely low, and the optic comes with a rear sight notch to cowitness the front sight in case the dot dies. 

All around you don't see any gap or questionable seamlines on this optic. So It's fully sealed front and back to prevent water and dust from getting into the housing unit.

Waterproof Performance

The optic is water-resistant, features an Closed emitter design, and is rated IPX 7.

Since we were testing this during the winter season, I had the opportunity to test it in the snow. For the most part, the optic performs in cold weather and there is no foggy lens during rapid temperature changes.

At the time of testing, the temperature went from 12 degrees to 63 degrees in the span of 3 hours, and there wasn't any visible fogging obscuring the lens.

So yes, it can handle snow and water if you accidently dropped it into a puddle. But this doesn't mean you can just pick it up and aim right away. 

You still need to wipe the lens clean before seeing through glasses clearly, and it way easier than dealing for example something like the open emitter where you have to dig things out and also clean the emitter screen.

Reticle Options

The Osight S now comes with a multiple reticle system and its operation mirrors the design for a Holosun product.

You get a single 2 MOA dot, a 32 MOA ring only reticle, and a combined reticle with the dot and the ring.

The 2 MOA dot appears sharp if you wear glasses. For those with astigmatism, the dot may not appear sharp if you have vision problems.

You can learn about the solution for astigmatism here, and I can tell you that most red dots are crystal clear if your vision is corrected. 

One thing I noticed was that the 32 MOA ring only option appears much easier for the eye to pick up than having to focus on the center dot if it appears refracted. 

As far as the buttons go, I can also press the "+" button for 3 seconds to cycle through:

• Manual
• Lockout mode
• Auto sensor mode

As far as brightness control goes, the max setting is plenty to see under a sunny day. The Flexible Light Sensor automatically adjusts the reticle brightness, but it doesn't change based on the target lighting conditions. 

Footprint

The Osight S has the RMSc footprint so it will go on any existing RMSc slides and mounting plates you already have. I think Olight made the right choice to go into the RMSc market in 2025 to offer price friendly options under $260 while other brands are selling them over $400 to $500.

This optic is mostly designed for subcompact handguns.

For detailed mounting specs please check out Olight's Official website here.

Turret

The first thing I checked was the turrets to see if they provide positive feedback because I think it's very important for an optic when it comes to zeroing.

This is a 1 MOA per click turret for both elevation and windage. 

I have tried some in the past that don't have positive feedback, and they are horrible at zeroing because I can't tell if I'm making 1 click or 2 clicks. They make a huge difference in accuracy.

The only complaint is that the turret requires a super thin flat head to dial. While trying to zero the optic at the range, I couldn't do it with a regular flat head screw driver or with a shell casing.

So if your using this optic, be sure to have a small flat head tool with you.

Battery Life

The Osight S is the first ever rechargeable RMSc red dot sight I have ever seen besides the SCS Carry and its way more affordable. Please a comment or send me an email if you think I'm wrong.

The battery is onboard the optic and it's rechargeable and it can last up to about 22000 hours if the brightness is set on mode 3. Obviously, not many people will use the optic on the lowest setting. 

So at about medium brightness setting, and leaving it there and stays on all the time. We can expect about only 10000 to 15000 hours if you carry it everywhere you go.

The only problem I see so far is that if you lose the USB recharging cover, then there is no way to charge the optic at all. For some this will be a deal breaker, so you better not lose it.

The charging cover is pretty unique and it has a indicator on top that shows the battery level. This is very cool and I haven't seen anything like this before in the gun market.

Final Verdict

The Olight Osight S is definitely very unique and it marks their first attempt to enter the RMSc red dot sight market with very low deck height for co-witness.

The large window design is definitely something that will attract many shooters who are looking for an affordable alternative to the EPS Carry and the ROMEO X Compact.

The battery life isn't the longest, but with its unique recharging capability it deserves some praises. However, the USB recharging cover is something you need to keep track of and don't lose it.

So far this product has very promising features and it looks and functions pretty good. It held zero under normal use and it functions just like any other red dot sights on the market.

The turrets dial precisely and the RMSc footprint direct mounting makes it very easy to mount on sub compact guns. Only time will tell if the Osight S will stand the test of time.

As you know, Olight has been very innovative in the past few years, and I feel confident that they will make another iteration to the Osight to make it better. (Check out their brand new Osight X with multiple reticle system for 2025)

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