I’m not going to lie, the FNX 45 Tactical is one of the nicest pistols I’ve ever held in my hands. It was also the first pistol I held with a red dot optic and at the time it was one of the coolest things I've ever seen.
It feels like the perfect combat weapon. The grip is the perfect shape and angle, and the texture of it is amazing. The double action, slide release, safety, trigger, and magazine just make it feel so cool and ready for action. Aesthetically I think it’s one of the nicest looking pistols I’ve ever seen, and the size is perfect.
I unfortunately do not own one (yet) but my good friend David does. David wanted to put an RMR on it but I convinced him otherwise. I don’t have any problems with the RMR, it’s a great optic, but for the price I told him you can get more for your money going the Holosun route.
He ended up putting a 508T Green on it (which is an excellent choice) but I showed him some other options as well.
So if you are interested in learning which Holosun Optics fit your FNX 45 Tactical and which we recommend keep reading.
FNX-45 Tactical Mounting Footprint
The FNX-45 Tactical comes with an optics ready slide and ships with two plates. One plate is a Doctor Cut which would fit a Burris FastFire 3 and the other plate is an RMR plate which would fit Trijicon RMR or any of the Holosun Optics we are about to recommend.
FNX-45 Adapter Plates (Optional)
One of the optics we’ll be recommending is the 509T which is Holosun’s closed emitter titanium optic. This comes with an RMR adapter plate, this means you will have your FNX-45 Tactical plate + the holosun adapter plate + the optic clamping on top of that plate.
To eliminate the need for two plates you can purchase a CHPWS 509T Adapter Plate. This plate will mount directly to your slide and then the 509T will clamp to it, this way you are not stacking plates and will have a lower deck height.
Why do we recommend the Holosun Optics vs other options?
- They are affordable but not cheap.
- They are built sturdily with strong aluminum or titanium housings and glass.
- They have convenient features like Shake Awake and Side Mounted Batteries.
- They have a Limited Lifetime Warranty.
- They are reliable.
- They are waterproof.
Top 8 FNX-45 Tactical Holosun Optics
The FNX-45 Tactical is a special gun. All the Holosun Red & Green Dot sights we mention here would be great for it but if you ask me personally, but my two favorites are the 508T and the 509T.
These are both made out of titanium which give them extra durability. I think they pair well with the gun since it’s a rugged, expensive gun to begin with, and pairing it with optics that are similar is a nice match.
Anyway here is a complete list of all the Holosun Optics that will mount directly to your FNX-45 Tactical.
1. Holosun 407C Red or Green
Buy the 407C At The Best Price
The 407C is the most affordable optic for the FNX-45 Tactical. It’s made with an aluminum housing, has a solar failsafe with auto brightness mode or manual mode, side removable battery, is waterproof and features a 2 MOA dot.
If you are a fan of the 2 MOA dot then the 407C may be all you need. If you are used to Trijicon RMRs this is very comparable.
- Aluminum Housing
- 2 MOA Red or Green Dot Reticle
- Up to 50,000 Hours Battery Life (Setting 6)
- 12 Brightness Setting: 10 DL & 2 NV Compatible
- Side Battery Compartment
- Auto Brightness Mode or Manual Mode
- Solar Failsafe™
- Shake Awake™
- IP67 Waterproof
Read our full 407C review here.
2. Holosun 507C Red or Green
Buy the 507C At The Best Price
The 507C is the next step up from the 407C. It is identical in features, but it has Holosun’s MRS Reticle (Multi Reticle System). This gives you the option to use a 32 MOA Ring + 2 MOA Dot, 32 MOA Ring only, or a 2 MOA Dot only. You hold down the “-” for three seconds to toggle between reticles.
The larger 32 MOA Ring makes it a bit easier to pick up the dot upon drawing the pistol.
- Aluminum Housing
- Red or Green Dot MRS Reticle
- 32 MOA Circle + 2 MOA Dot, 32 MOA Circle, or 2 MOA Dot
- Up to 50,000 Hours Battery Life (Setting 6 Dot Only)
- 12 Brightness Setting: 10 DL & 2 NV Compatible
- Side Battery Compartment
- Auto Brightness Mode or Manual Mode
- Solar Failsafe™
- Shake Awake™
- IP67 Waterproof
Read our full 507C review here.
3. Holosun 507C ACSS Vulcan Red or Green
Buy the 507C ACSS Vulcan At The Best Price
The 507C ACSS Vulcan is just like the 507C MRS except it has the Primary Arms ACSS Vulcan Reticle. This is a 10 MOA Chevron with a 250 MOA Outer ring.
When you look through the optic all you will see is the chevron. The chevron has a precise aiming point and acts as a BDC reticle. The 250 MOA outer ring is only visible when you do not have your dot centered. The ring is meant to act as a guide helping you find the dot quickly upon drawing the weapon. It’s a pretty cool system!
- Aluminum Housing
- Red or Green Dot ACSS Vulcan Reticle (learn more here)
- 10 MOA Chevron + 250 MOA Outer Ring
- Up to 20,000 Hours Battery Life
- 12 Brightness Setting: 10 DL & 2 NV Compatible
- Side Battery Compartment
- Auto Brightness Mode or Manual Mode
- Solar Failsafe™
- Shake Awake™
- IP67 Waterproof
Read our full 507C ACSS review here.
4. Holosun 508T Red or Green
Buy the 508T At The Best Price
The 508T is a step up from the 507C models. It features the MRS reticle, but it has two differences. It’s made out of titanium and it has a square shape. Both the shape and the titanium housing increase the durability of the optic. If you need a tough as nails optic, this is a good option for you.
- Titanium Housing (For Extra Durability)
- Red or Green Dot MRS Reticle
- 32 MOA Circle + 2 MOA Dot, 32 MOA Circle, or 2 MOA Dot
- Up to 50,000 Hours Battery Life (Setting 6 Dot Only)
- 12 Brightness Setting: 10 DL & 2 NV Compatible
- Side Battery Compartment
- Auto Brightness Mode or Manual Mode
- Solar Failsafe™
- Shake Awake™
- IP67 Waterproof
Read our full 508T review here.
5. Holosun 509T Red or Green
Buy the 509T At The Best Price
The next step up is the 509T. This is also made out of titanium and it’s built like a tank. The biggest difference between the others is that it’s an enclosed emitter. This means the emitter beam is covered by a protective hood. This keeps water, debris, dust, dirt, lint out of the emitter ensuring extra reliability.
For the best mounting set up we recommend getting an adapter plate like this CHPWS 509T Adapter Plate to eliminate the need for one of the plates. But the 509T will mount without the adapter plate with no issues.
- Enclosed Emitter
- Titanium Housing (For Extra Durability)
- Red or Green Dot MRS Reticle
- 32 MOA Circle + 2 MOA Dot, 32 MOA Circle, or 2 MOA Dot
- Up to 20,000 Hours Battery Life
- 12 Brightness Setting: 10 DL & 2 NV Compatible
- Side Battery Compartment
- Auto Brightness Mode or Manual Mode
- Solar Failsafe™
- Shake Awake™
- IP67 Waterproof
Read our full 509T review here.
6. Holosun 509 ACSS Vulcan Red
Buy the 509 ACSS Vulcan At The Best Price
Similar to the 509T is the 509 ACSS Vulcan. It is an enclosed emitter optic, but it has two major differences. It’s made out of aluminum and it has the ACSS Reticle (10MOA Chevron + 250 MOA Outer Ring)
It's worth mentioning that the 509T adapter plate we mentioned above will not work with this 509 ACSS Vuclan.
- Enclosed Emitter
- Aluminum Housing
- Red ACSS Vulcan Reticle (learn more here)
- 10 MOA Chevron + 250 MOA Outer Ring
- Up to 50,000 Hours Battery Life (Setting 6 Dot Only)
- 12 Brightness Setting: 10 DL & 2 NV Compatible
- Side Battery Compartment
- Auto Brightness Mode or Manual Mode
- Solar Failsafe™
- Shake Awake™
- IP67 Waterproof
7. Holosun EPS Red or Green 6MOA, 2MOA, MRS
Last but in no way the least is the Holosun EPS. This is Holosun’s latest closed emitter optic and is made out of aluminum. It has a lower deck height than the 509T and 509. It comes with an RMR adapter plate so it will mount directly on the FNX-45 Tactical, but you will have two adapter plates. It will be the slide > FN RMR plate > EPS RMR Plate > Optic.
The deck height will be the same as the 507C when using the adapter plate but it’s something worth noting.
These EPS models come in red or green and either a 2MOA, 6MOA, or MRS Reticle. The MRS Reticle has a solar failsafe and auto brightness mode, the others do not.
- Aluminum Housing
- Enclosed Emitter
- Red or Green Reticles
- 2 MOA, 6 MOA, or MRS Versions Available
- RMR Adapter Plate Included
- Modified RMSc Footprint
- Auto Brightness Mode or Manual Mode (MRS Versions Only)
- Solar Failsafe™ (MRS Versions Only)
- 10 Brightness Setting: 8 DL & 4 NV Compatible
- Side Mounted Battery
- Shake Awake
- IPX8 Waterproof
Read our full EPS Full Size review here.
8. Holosun 507 Comp Green & Red Dot - Largest Window Competition Reticle
Buy the 507 Comp At The Best Price
Next on the list is the Holosun 507 Comp. This is one of the newest and most sought after optics from Holosun. Comp stands for "Competition" because this optic features a VERY large window, meant for competition shooting. It's the largest window in the industry.
The 507 Comp has some key differences vs the other optics listed here. First it has the C.R.S. which is the Complete Reticle System. This gives it many reticle configurations like a 2 MOA Dot only or a 2 MOA dot + 8 or 20 or 32 MOA Circle or just a 8 or 20 or 32 MOA Circle.
The 507 Comp also does not have a solar panel on it which means there is also no auto brightness setting.
It has a 7075 aluminum housing, shake awake, a side removable battery, manual brightness modes, 10 daylight and 2 nightvision settings, and is IP67 waterproof.
This is a large optic.
Read our full 507 Comp review here.
9. Holosun 407C-X3 – Updated RMR Duty Optic
Buy the Holosun 407C-X3 At The Best Price
The Holosun 407C-X3 is the newest evolution of the popular 407C series, bringing several design improvements over the previous X2 model while maintaining the proven RMR footprint that fits most full-size pistol optic cuts and adapter plates.
The X3 version features a flatter top housing designed to improve durability and impact resistance compared to the rounded design of the earlier model. The optic also uses a blacked-out Holosun logo for a cleaner, more subdued appearance.
The optic sits approximately 1mm lower than the previous X2 version, giving a slightly lower deck height which can improve co-witness potential and overall presentation on many pistols.
The 407C-X3 uses a simple and effective 2 MOA dot reticle available in Red, Green, or Gold, providing precise aiming while still remaining fast to acquire.
Battery life has also been significantly improved. Powered by a CR1632 battery, the 407C-X3 delivers up to 100,000 hours of runtime on the dot setting at brightness level 6, roughly double the battery life of the previous X2 generation.
The optic is built from 7075-T6 aluminum and includes Holosun features like Solar Failsafe, Shake Awake, and automatic brightness adjustment, making the 407C-X3 a durable and reliable choice for range use, concealed carry, or duty pistols.
10. Holosun 507C-X3 – Updated RMR Multi-Reticle Optic
Buy the Holosun 507C-X3 At The Best Price
The Holosun 507C-X3 is the newest evolution of the popular 507C series, updating the previous generation with a reinforced housing and improved design while maintaining the proven RMR footprint used by most full-size pistol optic cuts and adapter plates.
The X3 version features a flatter top housing designed to improve durability and impact resistance compared to the earlier X2 generation. The optic also uses a blacked-out Holosun logo for a cleaner, more subdued appearance.
The optic also sits approximately 1mm lower than the previous X2 version, giving a slightly lower deck height which can help improve co-witness compatibility and overall presentation on many pistols.
The 507C-X3 features Holosun’s Multi-Reticle System (MRS), allowing shooters to switch between a 2 MOA dot, a 32 MOA circle, or the Circle-Dot combination. Reticle colors are available in Red, Green, or Gold.
Powered by a CR1632 battery, the 507C-X3 delivers up to 100,000 hours of battery life on the dot-only setting at brightness level 6, roughly double the runtime of the previous X2 generation.
The optic is constructed from 7075-T6 aluminum and includes Holosun features like Solar Failsafe, Shake Awake, and automatic brightness adjustment, making the 507C-X3 a durable and versatile option for concealed carry, duty pistols, or range use.
11. Holosun 407COMP – Large Competition Window 6 MOA Dot
Buy the Holosun 407COMP At The Best Price
The Holosun 407COMP delivers the same large competition-ready housing as the popular 507COMP, but with a simplified reticle designed for shooters who prefer a clean aiming point. It is also the most budget-friendly competition-style optic in Holosun’s lineup, coming in at a lower price than the 507COMP and 507PROMAX.
Built on the RMR footprint, the 407COMP fits a wide range of full-size pistol optic cuts and adapter plates while maintaining a low-profile mounting setup.
The optic features a large competition viewing window, giving a wide sight picture that makes it easier to track the dot during fast target transitions and recoil.
Instead of Holosun’s Competition Reticle System used on the 507COMP, the 407COMP uses a simple and effective 6 MOA dot. The reticle is available in Red, Green, or Gold, offering a bold aiming point that is easy to see during fast shooting.
Power comes from a side-loading CR1632 battery tray, allowing battery replacement without removing the optic or losing zero. Battery life is rated up to 50,000 hours on the dot-only setting.
The optic is built from 7075-T6 aluminum and includes Holosun features like Shake Awake, Lockout Mode, and brightness memory, making the 407COMP a strong option for competition shooters who want a large window optic without the higher price of the other competition models.
12. Holosun 507PROMAX – Largest Competition Window Optic
Buy the Holosun 507PROMAX At The Best Price
The Holosun 507PROMAX is designed for shooters who want the largest possible viewing window on a pistol optic. With a window size of 1.18 × 0.98 inches, it offers roughly 21% more viewing area than the 507COMP, making it the largest pistol red dot window currently available.
Built on the RMR footprint, the 507PROMAX fits a wide range of full-size pistol optic cuts and adapter plates while maintaining a secure, competition-ready mounting setup.
The optic uses Holosun’s Performance Reticle System (PRS), giving shooters multiple reticle choices including a 2 MOA dot, 8 MOA circle, 20 MOA circle, 32 MOA circle, and circle-dot combinations. The reticle is available in Red, Green, or Gold, allowing shooters to choose the reticle color and style that best fits their shooting preference or match environment.
A forward-leaning integrated sunshade helps reduce glare and improves reticle contrast in bright lighting conditions, while the enlarged window makes it easier to track the dot during fast transitions and recoil.
The 507PROMAX also features a solar panel unlike the 407COMP and 507COMP, which gives it Solar Failsafe and an auto brightness mode.
Power comes from a side-loading CR1632 battery tray with up to 100,000 hours of battery life on the dot-only setting. The optic is built from durable 7075-T6 aluminum and includes Holosun features like Shake Awake, brightness memory, and Lockout Mode for reliable performance.
13. Holosun AEMS-MACRO – Large Window Enclosed Competition Optic
Buy the Holosun AEMS-MACRO At The Best Price
The Holosun AEMS-MACRO combines the large window performance of competition-style optics with the durability of a fully enclosed emitter design. With a 0.9 × 0.9 inch viewing window, it provides a wide, square sight picture that makes it easier to track the dot during recoil and fast target transitions.
The enclosed emitter housing protects the LED from rain, dust, and debris, making the AEMS-MACRO a strong option for shooters who want the reliability of an enclosed optic without giving up a large viewing window.
The optic uses Holosun’s Multi-Reticle System (MRS), allowing you to select between a 2 MOA dot, a 32 MOA circle, or a circle-dot combination. The reticle is available in Red, Green, or Gold, giving shooters flexibility to choose the reticle color that works best for their environment and eyesight.
The AEMS-MACRO includes Holosun features like Solar Failsafe and a forward-facing light sensor for automatic brightness adjustment, along with Shake Awake technology for dependable performance.
Built from durable 7075 aluminum, the optic mounts using 509T footprint adapter plates.
Choosing between Red or Green Reticles
You may be wondering if you should get a red or green dot reticle. We get this question a lot so I am going to list a few bullet points for you to consider.
- Green reticles are less straining for the eye to see.
- Green reticles can help with astigmatism. If you have astigmatism you will see a blurry dot, we have been told by a few customers that Green dots help with their astigmatism, making the dot look more crisp than the red version.
- Green will not washout on backdrops like green grass, foliage, or green colors.
- In theory Green dots can have a longer battery life because Green is brighter, so for example a green dot on brightness setting 6 may be the same brightness as a red dot on setting 7 - which would save battery life.
If you want to learn more check out our full article about Red vs Green Dot Pros & Cons here.
Choosing between Open vs Closed Emitters
The simplest way we can break down open vs closed emitters is to look at how you plan on carrying the pistol. If you plan on being outdoors in the elements with rain, snow, sleet, then a closed emitter will be beneficial.
If you plan on carrying OWB most of the time and plan on being outside then closed emitter would be beneficial.
If you plan on carrying IWB or don't plan on being outside using your red dot in the pouring rain or heavy snow then an open reflex is fine.
Open reflexes will still work in the rain or snow but the closed emitter will give you extra peace of mind.
An open reflex can collect dust and debris on the inside of the reticle over time, so you'll want to clean it out from time to time. An enclosed emitter is easier to clean in this aspect.
To learn more about Open vs Closed emitters you can check out our Open vs Closed Emitter Guide here.
How to decide which reticle style is best for you
In this guide we covered a few different reticle options. If you need some help deciding which is best for you here are some of our thoughts on each.
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Conclusion
There are quite a few choices as you can see. If you still have questions please reach out to us and we can help you decide further.
Each optic has its own pros and cons. As we mentioned earlier, for the FNX-45 Tactical we think the 508T or 509T is best suited for it since they are the toughest optics in this lineup.
With that being said, you really can’t go wrong with any of the other ones.
If precision is your thing then we certainly recommend you check out the 509 ACSS Vulcan and 507C ACSS Vulcan as that 10 MOA Chevron point is the most precise reticle you can get.
Thanks for reading!
