Daily Deal: Die Free Co Dos Boot +2 PMAG Extension ~~$18.00~~ $14.00 - Get Yours!

MBUS® 3 FLIP-UP SIGHT SET FOR AR-15 Reviews & Ratings

The next evolution in the Magpul MBUS (Magpul Back-Up Sight) line, the MBUS 3 incorporates the best features, strengths and value of the original MBUS and MBUS Pro Sights in a feature-packed back-up sight system.

Significantly reduced in size from the MBUS, it sits at just 0.44” high when folded and 1.15” at its widest point. Its aesthetics are derived from the MBUS Pro, but the MBUS 3 Front and Rear Sight is constructed of Magpul’s impact-resistant polymer, making it lightweight and extremely durable.

Featuring the same spring-loaded technology as its predecessor, they can be deployed with an ambidextrous push-button. The MBUS 3 sits at standard AR-height when deployed.

The MBUS 3 Front Sight includes tool-less elevation adjustments and a dual width enhanced front sight similar to the MBUS Pro.

MBUS 3 Sights available in Black, Flat Dark Earth, Stealth Gray, and OD Green.
Made in the USA.

ELEVATION ADJUSTMENT

1.6 MOA (1.886"/100m) per click with a 14.5" sight radius
1.2 MOA (1.367"/100m) per click with a 20" sight radius

The MBUS 3 Rear Sight includes a rapid-select aperture system.

Rapid-select rear aperture system
0.44” high when folded
1.15” wide at widest point
Standard AR-height when deployed
Ambidextrous push-button deployment
• For attachment to M1913 picatinny rail

See all of our AR15s and AR15 parts here.

View Product

Write a review

Reviews Summary

Overall, the MBUS® 3 Flip-Up Sight Set has received mixed feedback. Many users appreciate their lightweight design and ease of installation but report difficulties with adjusting the sights and inconsistencies in fitting. While the sights are praised as solid backup options, some customers prefer the older MBUS models for better reliability and functionality.

What Reviewers Are Saying

Product Quality

60%

Reviewers have mixed feelings about the quality of the MBUS 3 sights. While some believe the sights are sturdy enough for backup use, others mention that they do not meet the quality standards of other models, particularly citing installation issues and difficulties with adjustments.

Installation Challenges

45%

A substantial number of reviewers faced installation difficulties, specifically with the tight fit on various rail systems. Some recommended using tools or modifications to make them fit, which detracted from the overall user experience.

Ease of Use

50%

Several customers noted that while the sights are generally easy to install, they had issues with front sight adjustments being too tight or malfunctioning. The rear sight, however, was praised for its improvements over previous models, leading to easier switching between apertures.

Comparison to Previous Models

55%

Many users compared the MBUS 3 to MBUS 2 and noted improvements in design and functionality, but some still favored the older versions for their reliability and ease. The overall sentiment is that while the MBUS 3 has benefits, there are concerns that affect its usability.

Value for Money

35%

The pricing of the MBUS 3 sights is frequently mentioned as a positive aspect, with many reviewers asserting that they are a great budget-friendly option for backup sights. However, some concern exists regarding their long-term viability at this price point.

Sort by Filter by rating

What happened?

Magpul... what happened!?! I have mutiple gen2 mbus, and they are great, but the gen3 front sights are junk. Adjustment is sloppy and literally feels like it may fall apart. Like I mentioned, I have multiple gen 2 mbus and when my Dad asked what backup sights to get, I said magpul, definitely! I coached him to get the gen3 based on magpuls reputation, but I wish I hadn't! The front sight is all but unadjustable. It's third world junk level, and to say I was disappointed would be a serious understatement. I hope that this was a developmental glitch and magpuls quality remains, but at this point, I have my doubts. This is no better than the cheap amazon imitations, and maybe not as good! Please step up your game Magpul, or you'll be just the latest company to fail by riding a reputation into the ground. These sights are absolutely horrible! I never thought that I would have to say these things about magpul.

Front sight

Even after reviewing many posts on the subject, the front sight is still nearly impossible to adjust.

by JOSEPH A. on December 05, 2025

Verified Purchase

Was this review helpful? 0

MBUS 3 Flip-Up Sight Set

I bought these as a gift for Christmas for a family member. When trying to install the sights on the standard 1913 picatinny rail, it did not fit on a Std AR rail system. Tried them on a second AR rail, and the same issue. Sight went on a little, and then became lodged and wouldn't move any further. Even got stuck on the 2nd rail and took a lot of effort to get it back off. Also had a set of the Gen II's that were given as a gift as well, an those worked without any issues at all. Also, these Gen III's do not have the nice convenient thumb tabs on the side for a quicker deployment of the sights. I saw where another person had the same issue in a Glock forum on a similar upper and people were recommending using a mallet to get them on, putting them in hot water to expand the plastic, and even putting the upper in a freezer to get everything to work. I am not going that far Had to return them, and ended up buying the older Gen II's which work very well and have the quick release thumb tab on the side. I do not recommend these

by Wes U. on December 26, 2024

Verified Purchase

Was this review helpful? 2

Front Sight Defective, Rear sight Too tight to install.

Front adjustment wheel was frozen. Impossible to make elevation changes (it did however produce nice groups 6" low on target). Rear sight was too tight to install- required significant filing to get it to fit. Worked perfectly once installed. All other Magpul MBUS sights I've owned fit and worked fine. I don't know if this was a one-off issue with this specific set, or a problem with this particular model (MBUS 3) sight.

by GARY B. on March 28, 2024

Verified Purchase

Was this review helpful? 4

On target

Good to go. I prefer the front sight adjustment on these Gen 3.

by DAVID E. on January 02, 2024

Verified Purchase

Was this review helpful? 0

MBUS 3 FRONT & REAR SIGHT SET

Front sight post adjusting nut won't turn to adjust post height making sight useless. Rear sight horizontal adjust knob works ok.

by JIM S. on August 05, 2023

Verified Purchase

Was this review helpful? 11

Front sight does not fit

Purchased both front and rear MBUS 3 sights. Rear sight fit picatinny rail perfectly on Foxtrot Upper. The front sight was another story. After many attempts the front sight would not fit on the rail. Seems to be a difference in quality construction between the two sights. I guess I will return back to the earlier versions I have used in the past ( at least 12 sights on various At-15s.