Shield Sights Ltd is a United Kingdom-based company that has produced over 100,000 SMS sights alone. Over 15,000 sights are currently in active use by military and special forces.

The company remains dedicated to advancing compact and lightweight sights, frequently introducing new models. I’ve made this review to test the available sights and highlight distinctions between various models.

Shield Sights Red Dots Review: SMS2, RMS, SIS2, RMS, RMSx, RMS Compact: Handgun, Rifle, Shotgun

From the smallest to the largest of the sights.

Shield Sights Red Dots Review: SMS2, RMS, SIS2, RMS, RMSx, RMS Compact
From RMS Compact to Switchable Interface Sight.

SMS 2.0, RMS 2.0, RMSc

Every day carry or backup sight for rifles, pistol caliber carbines and even shotguns.

  • SMS2 stands for Shield Mini Sight, 2nd version. It has polymer body.
  • RMS2 stands for Reflex Mini Sight, 2nd version. It has aluminium body.
  • RMSc stands for Reflex Mini Sight Compact. Slimmer design for compact handguns, aluminum body.

There are two types of lenses: one made of plastic (polymer) and another with glass (Glass Edition). The plastic lens is good and durable, but you have to be careful when cleaning it to avoid scratches. The Glass Edition is more resistant to scratches, but it costs more. I like it better, though.

The SMS2 sight is the most inexpensive one from Shield sights. It’s lightweight because it’s made of plastic, and it’s tough enough for heavy use. RMS2 is little more expensive because of the aluminum body.

Even though it was made for handguns, its small size makes it good for many other guns too. I’ve seen it on all sorts of guns, like handguns, rifles, pistol caliber carbines, and even shotguns!

Shield RMS2 and SMS2 Sights

Shield RMS2 and SMS2 Sights


Mounting on handguns which can accept optic sights, such as GLOCK with Modular Optic System (MOS) or Canik with an Optic Ready Slide, is straightforward. However, if you want to mount it on a Picatinny rail, you’ll need an additional adapter, which is available for purchase separately.

Picatinny Vented Mount & Spacers

Remember that you will need longer screws (included) to attach sight to the mount with spacers.
There are even rubber washers for installation screws to protect your sight from scratches. Make sure you are using them.


Zeroing Red Dot Sight

Zeroing Shield SMS Sight

(Shield SMS sight with Wing Mount which provides protection against side impacts)

Zeroing is very simple with included Minidial and wrench. Even the complete newbie can do it using the hints on the Minidial:

Dot Up / Group Down
Dot Right / Group Left

Brightness Adjustment

The SMS sight features automatic brightness adjustment, which is convenient as it eliminates the necessity of manually tweaking the dot brightness based on ambient light conditions. However, the only drawback I found is when you are shooting from shadow in a bright day, then you may want a brighter dot.

Backup or Additional Sight for a Rifle (AR-15)

As a practical shooter (IPSC) myself, I have used it as an additional sight for competitions. It serves two purposes.

First, it allows you to quickly hit close targets without adjusting the primary optic sight. This significantly saves time during transitions from distant targets to nearby ones.

Second, it works perfectly when you need to hit the hidden target on the left side of the barricade. It saves a lot of time and eliminates need of transition to a weak shoulder.

Also, it is one of the best backup sights which can save your day when something goes wrong with your primary optic. Light weight and compact size make it almost invisible. All you need is a 45 degree offset picatinny rail to attach it to your rifle.

AR-15 SMS Sight

Main and Additional Sights for a Pistol Caliber Carbine (PCC)

Pistol Caliber Carbine is a very popular type of firearms now. It was added to IPSC and there are a lot of competitions around the world.

I have used SMS sights on my Inter Ordnance for a long time. Again, as you can see, I use two sights to help me when I shoot targets from unstable positions.
They are compact, lightweight, so there’s no problem having several of them.

The only problem with open sights is that you cannot use them during rain or snow. It happened to me on a training once. A snowflake fell directly on diode and dot disappeared.
If you need a red dot sight for heavy conditions, then Shield SIS will better suit your needs.

Shield SMS Sights on a PCC
(This setup may look funny but it really helps getting that difficult target without transition to weak shoulder)

Sight for Shotguns with Vent Rib

A lot of shotgun shooters started looking for red dots when IPSC rules were changed and electronic sights were allowed in Modified division.

SMS or RMSx (it will be described below) suits needs of shotgun shooters. It can be installed on any vented rib using the special mount.

It is handy upgrade not only for competitions, but for hunting too. You can choose one of several reticles available from dot to ring with dot.

Benelli M2 with Shield SMS Sight
(My friend using the SMS sight on his Benelli M2 for the first time)

Time has shown that 12 gauge recoil is something Shield sights can handle without any problems.

Benelli M2 with Shield SMS Sight

Polymer Shotgun Mount for SMS/RMS sights can be replaced with custom aluminum mount which is more reliable and holds sight in place under heavy shotgun recoil better.

RMS Compact for Handguns

This is slimmer version of the RMS sight for such handguns as Glock43, Smith & Wesson shield, and the 1911.
Other than that you have all the features which standard RMS sight provides.

RMS and RMSc Comparison
(RMS and RMSc Comparison)

RMSc gives a lot of advantages when mounted on an everyday carry (EDC) handgun. It allows faster and more precise target acquisition. This is particularly useful in high-stress situations where split-second decisions matter. It is made of aluminum and feature rugged design to ensure reliable performance in various conditions.

Shield RMS Compact for Handguns

Shield RMS Compact for Handguns

Shield RMS Compact for Handguns

You can choose 4 or 8 MOA dot.


Designed for competitions, for shotguns, rifles or handguns. The interesting thing is that you can get the RMSx sight in different colors.

  • RMSx stands for Reflex Mini Sight with XL lens.

It has aluminum body and huge lense (80% bigger than regular RMS lense) which was specifically designed for competitive shooters.
XL lense allows faster aiming, target acquisition and transitions from one target to another. Because of its extreme thinness, the frame is almost invisible while shooting.

Shield RMSx Sight

It has all of the advantages of the SMS and RMS sights: automatic brightnes adjustment, compact size and light weight.

Glass Edition which I was testing is more resistant to scratches. Cleaning and maintenance is also easier for me. I am using sight with 65/2 MOA Ring and Dot RMSx reticle which is great not only for shotguns but for pistol caliber carbines too. I have found it very nice when shooting at both paper and metal targets.

This is my new favourite sight for practical shooting. Whether it’s a Pistol Caliber Carbine or shotgun, I like it! The lense is big enough to enable you shoot as fast as possible.
The quality of lense is perfect, I can have a clear picture and focus on shooting.

RMSx Reticle
(65/2 MOA Ring and Dot RMSx reticle)

You can also choose 4 or 8 MOA dot.

RMSX on Pistol Caliber Carbine

Field of view is bigger compared to Shield SMS and enables you to shoot faster. I have replaced my SMS sight with the RMSx sight and immediately saw the difference.
Bigger lense made my first shot, transitions and overall performance better. It even makes shooting from unstable positions easier (if you don’t have the additional canted sight).

Shield RMSx Sight on Vented Mount

RMSX on Shotgun Vent Rib

SMS was good for shotguns but RMSx is perfect. It is small and low profile and enables you to shoot targets easy and fast. You can switch from regular fiber optic sight to RMSx really fast. The migration is easy because shouldering, position of your head and other things are almost the same.

Shooting slugs is easier than ever! With a red dot you can hit targets on a longer distances much faster.

So, it’s perfect choice for Modified Division in Practical Shooting (IPSC).

RMSX on Shotgun Vent Rib

RMSx sight can withstand the heavy 12 gauge recoil and I am sure that it will work for many years and thousands of shots.

The design is also very nice and I like how it looks on my firearms.


Heavy duty sight for rifles or pistol caliber carbines (AR-15, AR-9, MP5, etc.)

SIS2 stands for Switchable Interface Sight, version 2.0. The sight has 4 switchable reticles (1 or 4 MOA dot with or without 65 MOA ring of dots) and auto or manual brightness adjustment settings with two buttons.

This is the further development of the CQB/CQS sights. Closed sight design completely enclose the diode in a metal casing protecting it from damage, dirt or water. This sight is rock solid and you can find torture test on YouTube. Sight works in any conditions and can withstand a lot of abuse.

Choose this sight if you plan to use it in harsh conditions and want to have additional reticles or manual brightness adjustment.

Shield SIS2 Sight

Picatinny rail adapter included. So you can install it on your gun right away.

You can use any screwdriver or coin to zero your sight with special slots for elevation and windage.

HK MP5, MKE T-94, Zenith Firearms ZF-5

I always wanted to have a compact red dot sight on my MP5 pistol caliber carbine. But all the mounts on the market were big and bulky.
This new mount from Shield Sights is fantastic. It is easily attaches to the firearm, it is low profile and compact.

The best sight for such reliable gun as MP5 is a SIS sight in my opinion. MP5 is a gun for home defense or tactical use, so it need the more reliable sight possible.
This SIS sight is perfect for this purpose.

Shield SIS on HK MP5 Mount

MP5 Shield SIS Co-witness
(MP5 Shield SIS Co-witness)

When installed with HK MP5 Mount you can use both reflex sight and iron sights. This feature is good if you damage your sight somehow or when battery depleted disabling the reticle.
This makes MP5 and SIS setup even more reliable.


I can recommend Shield Sights for many purposes, from competitions to home defense. There are a lot of different models available and I hope that this review will help you to choose the right one.

Advantages of the Shield Sights

Clear, high-quality lense
Lenses on sights are clear and don’t have any distortion or tint.

The sights are always on
When in urgent need of shooting, with no time to press the power button or adjust the dot’s brightness you don’t need to worry. The Shield sights are always on, just remove the cap and you are ready to shoot. Also, they adjust brightness automatically saving you time.

Battery life:
All 1, 4 & 8 MOA mini sights – 2 years
65/1MOA mini sight and the SIS – 1 year

Sights are compact
All sights are small and low profile enabling you to install them on any firearm. That’s why they are using a CR2032 lithium battery.

They are lightweight
They add virtually no weight.

I had about 500 shots on my new RMSx sight and several thousands on my SMS sights. They hold zero and really fun to shoot.
Shield sights are reliable and have very good reputation. I had minor problem with one of my sights but it was repaired quickly.

So if something goes wrong, you can always contact support and get that problem fixed.

Disadvantages of the Shield Sights

Polymer lense was easy to scratch
This problem was fixed when Glass Edition came out.

You need to remove sight to replace the battery
Not really a problem for me. I can do that once a 2-3 years.

High price
Price can be compared to price of other sights. But remember that sight is made in UK and you have Limited Lifetime warranty on materials and workmanship and 7 year warranty on electronics.

More information about sights and ordering: Official Shield Sights Website