Osight K Green: Sub-$170 6 MOA RMSc Green Dot Sight

Osight is releasing a 6 MOA green dot version of the K, its lowest-cost open-emitter RMSc pistol optic, at a $169.99 MSRP. The K launched as a red-dot-only optic; the green K is the same housing, battery, and footprint with a green emitter swapped in. Osight is running a launch promo that drops the price to $144.49 from July 13 through 17, 2026. Osight also offers an RMR-to-RMSc adapter plate as a separate accessory for full-size RMR-cut slides.

Osight is the firearms-optics sister brand of flashlight maker Olight, headquartered in Phoenix, Arizona. Over the past year it has undercut Holosun and Trijicon across its enclosed and open-emitter carry optics, and the K is the entry point to that line. Green emitters normally cost more to produce, which is why the green K carries roughly a $10 premium over the $159.99 red K. If you are still weighing dot color and footprint, our guide to the best pistol red dot sights covers how the RMSc cut and reticle size affect carry-gun performance.

Green and red reflex dots deliver the same speed and accuracy; the reason to choose green is visibility. The human eye is more sensitive to green light, so a green dot often appears brighter and is easier to acquire against dark targets, foliage, and cluttered low-contrast backgrounds. Many shooters with astigmatism also see a green dot as a cleaner point instead of the smeared starburst a red dot can produce. The tradeoff is small: green emitters draw a bit more current and add roughly $10 to the price.

On a 6 MOA carry optic, that green advantage lines up with the optic's purpose. The 6 MOA dot is the largest single-dot reticle Osight offers, sized for a fast, forgiving aiming point at defensive distances rather than precision bullseye work. Pair the largest dot with the more eye-friendly color and you get the quickest possible pickup on a draw. If you rarely lose a red dot in your normal light, the $159.99 red K does the same job for less; if you do, the green K is the upgrade.

The K Green runs a side-loading CR1620 that swaps from a tray on the side of the optic, so you replace the battery without pulling the dot off the slide and losing your zero. A motion sensor wakes the reticle the instant the gun moves and powers it down after three minutes of stillness, and a low-power indicator triple-flashes once a minute once voltage drops below 2.2V. Eight daylight and two night-vision brightness levels cover the range from a bright range day to passive aiming under NODs.

The K Green uses the Shield RMSc footprint, the standard cut for slim optics-ready pistols. It direct-mounts to optics-ready, RMSc-cut slides, including the SIG P365 XL and P365-XMACRO, the Glock 43X and 48 MOS, the Springfield Hellcat OSP, and the S&W Shield Plus OR, and an optional RMR-to-RMSc adapter plate, sold separately, lets it ride full-size RMR-cut slides too. Confirm your slide's cut before you order: the RMSc footprint and the smaller Holosun-K pattern are not interchangeable, and mounting the wrong footprint is the most common carry-optic mistake. Browse the pistol optics catalog or use the builder to check how the K Green fits alongside the rest of a carry setup.

The K Green is the cheapest way into an Osight green dot, and it anchors the bottom of the pistol line below the enclosed SE and the multi-reticle XE. Its one real compromise is the open emitter: the exposed LED notch is more exposed to lint, dust, and moisture than a sealed optic, and the IPX6 rating trails the IPX7 sealing on the enclosed models. If you carry daily in a pocket or appendix and want a green reticle that shrugs off debris, step up to the enclosed SE Green. Our best enclosed-emitter pistol red dots guide lays out where a sealed window earns its price.

Against outside competition, the K Green undercuts the green-dot versions of the Holosun 407K and Swampfox Sentinel while offering the same 6 MOA dot and RMSc footprint. We covered Osight's broader push into enclosed carry optics when the brand launched the XE AMRS and SE 6 MOA, and you can compare optics side by side to line the K Green up against your current dot. A hands-on review of the K Green is coming soon.

The K Green is a narrow, sensible addition: the exact optic shooters already buy for its price, now with the reticle color that picks up faster for a lot of eyes. At $169.99 MSRP, or $144.49 during the July launch window, it is one of the least expensive green dots that still brings a side-loading battery, motion sensor activation, and slim-slide RMSc fit. The open emitter and IPX6 rating are the ceiling on it; if that matters for your carry conditions, the enclosed SE Green is the next step up.

The standing caveat for any Osight is track record. The brand is young, and the decade of armorer reports that back a Trijicon or Aimpoint does not exist yet. For a slim carry gun where you want a large, eye-friendly green dot without spending north of $250, the K Green is an easy value pick. Cross-shop it against the field in our best pistol red dot guide before you commit.