Primary Arms SLx Full Size 3X Magnifier

Manufactured by Primary Arms
MPN: 510012
Manufactured by Primary Arms
5 Reviews

In Stock

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The SLx FS 3x Magnifier supplements your red dot or 1x prism with added magnification when engaging targets at medium to long distance. This magnifier is part of our SLx optics line. SLx optics built our reputation for innovation, reliability and value. All SLx optics undergo rigorous field-testing during development to best serve you in any environment.

Compatible with the most popular mounts on the market, the SLx FS 3x Magnifier is a versatile addition to any close-quarters optics setup, and the enhanced glass quality and wide field-of-view ensure that the user can always get a clear view of their target. Though the SLx FS 3x Magnifier weighs a mere 8.45oz, its durable construction protects it against the repeated shocks and impacts of duty use.

As with all other Primary Arms Optics products, this magnifier comes backed with a limited lifetime warranty and commitment to customer satisfaction.
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BrandPrimary Arms
Exit Pupil Diameter8.50 mm
Eye Relief2.80 in
Field View 10040.5 ft.
Manufacturer.Primary Arms
Weight8.45 Oz
  • New SLX 3x MFS

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see

Ratings & Reviews

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PA SLX 3X Magnifier

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Got mine today. Works perfectly with a G2 Cyclops and the PA mount for the 3X. Very clear glass. Took about 5 minutes of fiddling to mount and adjust the diopters. Perfect 3X sight picture. Remember to run the diopter on your Cyclops as far OUT as possible while still keeping a clear sight picture, then start with your diopter on the 3X all the way IN and back it out until your reticle and sight picture are focused and clear. A magnifier behind a Prism sight can be fiddly to get adjusted (lots of lenses to align and adjust), but his combo works like a charm.

Amazing clarity

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The clarity on this magnifier is better than on the SLx 3-18x50mm FFP ACSS Athena BPR MIL, it's crazy to get this performance out of a magnifier. There's true edge to edge clarity. This optic is also using proper thread inserts instead of helicoils.




Excellent magnifier!

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Picked this up with the reccomended flip to side mount to pair with the PA micro prism 1x. I was skeptical of it would work with a prism, but after mounting it and finding the right combinations of adjustments on both the magnifier and micro prism, I got the reticle and magnified image to come in very clear! I love it and couldn't be happier especially for the price. Glass quality is great and the overall feel, fit, and finish is top notch. Will be buying more of these for other ar's in the future!

Excellent value

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Marshall recommended this over the LER 3x I had been waiting to come back in stock. He was right. I have it magnifying my Gen 2 prism. Glad I went this route. I needed the small spacer for the slx gen 2 scope.