Chad Wallace

July 12, 2026

Optics, review

Primary Arms SLx 1X MicroPrismT

Chad Wallace

July 12, 2026

Optics, review

Primary Arms SLx 1X MicroPrismT

With RDB T-Dot reticle

If you have read any of my previous reviews, you know I am a fan of 1x MicroPrism optics. Primary Arms has updated their SLx line of MicroPrisms. These new prism optics have standardized mounting footprint. One of these new prisms has a Red Dot Bright (RDB) reticle. That particular one is the Primary Arms SLx 1X MicroPrismT with RDB Illuminated T-Dot Reticle.

As with all of the Primary Arms MicroPrisms, they come with everything needed. You get scope caps, wrenches, a battery, and a way to mount it. The “T” in MicroPrismT designates the new mounting footprint for these prism sights. “T” is for the standard T1/T2/H1 Aimpoint Micro mounting footprint. This allows the SLx T prism to attach to any of the mounts that use this footprint, and there are a ton of them. Besides that, the SLx MicroPrismT comes with a very nice 2.26 inch high mount. This is one of those “heads up” style mounts and is very usable.

New in the SLx MicroPrismT is the T-Dot reticle. It is called a “T-Dot” because the lines in the reticle form a T shape. And guess what, where those T lines almost intersect, there is a 2 MOA center dot. It is a super simple and fast reticle. There are no marks for hold overs or bullet drops, making it even more like a red dot. The SLx MicroPrismT also has the new RDB dot, or “Red Dot Bright”. Since this is the T-Dot reticle, only the center dot is illuminated with the RDB system. When Primary Arms says “Red Dot Bright”, it really is that bright.

In the adjustment department, nothing has changed over the original SLx Prisms. You still get a diopter to adjust the clarity of the reticle to your eyes. The Brightness setting is still combined with the battery knob. So the battery sits inside the brightness knob. It still has 13 levels, with the bottom 3 being used for night vision. The top settings are now brighter thanks to the RDB system. The brightness knob is pretty stiff with not great detents. But you really do not need to worry about that since Primary Arms did include their “Autolive” system. So the reticle will turn off automatically and then turn back on when it senses motion. Reticle adjustments are the same 1 MOA clicks as in previous SLx prism optics.

Primary Arms has not changed the glass quality on the new T prisms, but they didn’t need to. Looking through the SLx MicroPrismT is still super clear. It is still a true 1 power reticle, so what you see is exactly what you see through the prism. The SLx T-Dot is also an etched reticle. This has a couple of advantages. One is that the reticle doesn’t need power to be seen. Of course you don’t get that red dot glowing, but you still have something to aim with, unlike a regular red dot. The next advantage is that people who don’t see red dots clearly, will usually see etched reticles clearly. The last advantage to the SLx line of prisms is that they can use Back Up Iron Sights (BUIS) and/or a magnifier.

I ended up mounting the new SLx MicroPrismT on a Foxtrot Mike Mike-15 Gen 2. It replaced a regular red dot that was on the rifle. I really like 1x prisms on AR style pistols, so the SLx fit the bill perfectly. I really like the T-Dot reticle, not just because it is bright, but because it just works. I would prefer more of a circle dot reticle where just the center dot illuminates, but they didn’t ask me. One of my favorite aspects of the Primary Arms prism optics is their incredible eye relief. They state 2-7 inches, but it is essentially anything. This makes it work great for speed and odd positions because you don’t have to worry about where your eye is in relation to the optic. On that note, the MicroPrismT comes with a 2.26 inch high mount. It is a nice mount, but too high for my liking on the Mike-15. Good thing it uses T1/T2 mounts so I can get whatever height I want.

The Primary Arms SLx 1X MicroPrismT is a really nice 1x prism. The reticle is simple to use. Being an etched reticle helps make it super clear for people with eye anomalies. The industry standard mounting footprint gives you plenty of options, especially if you don’t like the supplied 2.26 mount. Lastly, that RDB lets you see the dot in any lighting conditions. If you are looking for a true 1x prism, I would check out the new Primary Arms SLx 1X MicroPrismT with RDB Illuminated T-Dot Reticle. With the performance you get from the Primary Arms Prisms, you can’t beat their value.

Firearms Insider Reviews - Key Points

Claim to Fame:

1 power prism optic with a simple to use, daylight bright reticle

Target Market:

Anyone wanting an etched reticle 1 power optic that can be seen in direct sunlight

Features, Benefits, and Specifications of this product:

H1/T1 optic footprint
Magnification: 1x
Objective Lens Diameter: 17mm
Eye Relief: 3.6" (Usable Range: 2" to 7")
Exit Pupil: 15.6mm
Field of View: 76.5 ft @ 100 yards
Length (w/o lens covers): 2.48"
Weight (with battery, w/o lens covers): 5.5 oz
Illumination: 13 settings (3 NV-compatible), Red Dot Bright
Reticle: T-Dot (etched glass)
Click Value: 1 MOA
Total Elevation/Windage Adjustment: 120 MOA each
Battery: 3V CR2032
Mount Footprint: H1/T1 micro dot compatible
Construction: Aluminum alloy with hard coat anodizing
Waterproof: IP67 / Nitrogen purged / Dustproof
Includes: 2.26" mount

What other aesthetic options or finishes are available?

Both red and green in ACSS Cyclops and Gemini reticles. These are not Red Dot Bright (RDB) reticles

What others are saying?:

5 out of 5 stars on Amazon

Great optic, no low mount actually included

Awesome optic. Insanely crisp reticle for someone with astigmatism. Did not think I would ever see a reticle be so clean. Great glass and great mount as well. One thing to know is that the info here on Amazon, the packaging, and the manual all state that a low mount is included. This is incorrect, as only the high mount pictured is included. This info is posted on PA's webpage for this product. I just wanted to let anyone looking at this optic know that in case they were counting on the low mount. Five stars for me as I didn't need the low mount and the optic is otherwise exactly as described. Excellent optic for an excellent price. Would recommend, if you don't need the low mount that is.

Link to other reviews:

Athlon Outdoors

Price point:

MSRP = $279.99

Retail = Same

I need it now! Availability:

Primary Arms or Amazon

Our Rating:

Pros:

Super Bright
Clear reticle
Industry standard T1/T2 footprint
Great Eye Relief
Can be used with BUIS and magnifiers

Cons:

Smallish objective lens
Stiff brightness knob

Score: 8.50 Great

Favorite Link: Primary Arms SLx 3x Prism review

Chad Wallace

July 4, 2026

Optics, Review, Gear

ZeroTech Thrive HD 1x Prism

Chad Wallace

July 4, 2026

Optics, Review, Gear

ZeroTech Thrive HD

1x Prism Review

If you did not already know, ZeroTech Optics has a 1x prism. ZeroTech has recently expanded the Thrive HD 1x Micro Prism with a Flat Dark Earth version. Since I really like prism optics, I had to get one and see how it compared. Plus, the FDE version caught my eye and looks really nice.

As with most prism sights nowadays, the Thrive HD comes with all the normal features. You get soft touch buttons. A side load battery tray. An adjustable diopter so you can see the illuminated reticle clearly. It specs out a 50,000 hour battery life with an auto awake/sleep feature. Plus it comes with a nice little neoprene cover, which I have misplaced.

The Thrive HD prism comes with a pretty standard style reticle. It is a large circle dot etched reticle style with short lines that break up the circle every 90 degrees. It works well for getting on target fast, but does have a few shortcomings. The dot portion of the reticle uses a nice 3 moa dot. The dot gives a good compromise between speed and accuracy. Since the circle portion of the reticle is large, 110 moa, it limits its use on something like an AR style rifle. I say this because there are no good reticle marks for height over bore at 5-10 yards. However, with the dot sighted in at 100 yds, the lower stadia and circle are good for 500-600 yard shots. If you install the prism on a pcc or something that you are only shooting out to 100 yards, just sight the dot in at 25 or 50 and call it good. The Thrive HD is still a good all around 1x prism.

As mentioned previously, the Thrive HD has all the latest tech. Shake awake, 50k battery life, easy battery changes, and soft buttons. It also has red illumination for the etched reticle. There are 13 illumination settings, so you can get it as bright or as dim as you like. Even though it is technically not a daylight bright reticle. It is bright enough to be seen on most days, unless the sun is fairly bright. But since the reticle is etched, you will always see the black reticle, even if your battery dies or you decide to aim at the sun.

Even though the ZeroTech Thrive HD prism is stated to be 1 power, it is not. This is my biggest complaint. It is more like a 1.1-1.2 power optic. This makes you see a double image if you try to look at something close up, with both eyes open. As you get farther out in distance, it is not noticeable. With anything closer than 20 yards, I had to close my non-dominant eye so it didn’t bother me. Besides that, the Thrive HD prism is super clear. I wonder since it is so clear, if that is why, at close distances, I see a slightly magnified image? The 20mm objective lens gives decent light transmission. It also makes finding the reticle fairly easy.

The Thrive HD 1x Prism is in the new style of prism optics. This makes it possible to use back up iron sights. Yes, you can see the sights through the prism, even if they are a tiny bit fuzzy with the Thrive. The other big advantage to these new prisms is that you can put a magnifier behind them, thus giving you more magnification.

When you think about prism optics, weight might be a concern. The Thrive HD tips the scales at 7.55 ounces. This is right in line with other prism sights. A big advantage to the Thrive HD is that it comes with 4 different mounting height options in the box. If one of these heights doesn’t fit you, the Thrive HD is compatible with Aimpoint T2 footprints. Thus giving you endless mounting options.

When testing the Thrive HD prism I mounted it on the MAC IX. I figured this would be a good platform for it, and it was. This also helped show me the not true 1 power magnification. I will probably mount it on a rifle at a later date, since I only use the MAC for closer in shooting. I really liked that it came with a bunch of different height mounts, especially since the brace on the MAC sits a little lower than an AR stock. Part of the reason I like prism optics is that the etched reticle doesn’t flare out because of my astigmatism. The Thrive HD prism’s reticle is super clear for me. I also like the auto awake feature. Not just because it extends battery life, but because I don’t have to remember to turn it off or on. Lastly, the FDE color on the prism looks more burnt bronze to me. I actually like the color. Besides, it adds another shade of FDE to the already 50 shades out there.

The ZeroTech Thrive HD 1x prism, in FDE, is a nice optic. It is super clear and bright. Even if it really isn’t a true 1x power, it is still a nice prism optic. It comes with everything needed to mount it up, sight it in, and go blast some trash. So if you are looking for a new prism sight, take a look through the Thrive HD 1x Prism and see what you think.