Summer Cleanout Sale!
Huge Savings On 2000+ Items From 200+ Brands - SHOP NOW

Daily Deal: Brownells Acraglas 2-Gun Bedding Kit ~~$27.99~~ $21.99 - Get Yours!

MBUS Front Sight Flip-Up Polymer for AR-15 Black

MBUS Front Sight Flip-Up Polymer for AR-15 FDE

MBUS Front Sight Flip-Up Polymer for AR-15 ODG

MBUS Front Sight Flip-Up Polymer for AR-15 Stealth Gray

MAGPUL - MBUS® FLIP-UP FRONT SIGHT FOR AR-15

7 Reviews

Color

Black
Dark Earth
O.D. Green
Gray

Brownells #

100006791, 100006792, 100006793, 100014400

MFR #

MAG247-BLK, MAG247-FDE, MAG247-ODG, MAG247-GRY

UPC

873750004310, 873750004327, 873750004334, 873750011486

$28.99 - $29.99

Purchase Limit

In stock

NOTIFY ME WHEN IT'S BACK IN STOCK

Can we ship this to you? (US only)

How To Buy Guns Online

International purchase information

What is the MAGPUL - MBUS® FLIP-UP FRONT SIGHT FOR AR-15?

The MBUS (Magpul® Back-Up Sight) is a low-cost, color injection-molded, folding back-up sight. The MBUS Front Sight is adjustable for elevation and fits most 1913 Picatinny-railed hand guards, but is specifically tailored to the AR15 / M16 platform.

An elevation adjustment tool is included, but most aftermarket A2 front sight adjustment tools may be used as well.

FEATURES

Spring-loaded flip up sight
Easily activated from either side or by pressing the top
Protective wings shield the spring-locking A2 front sight post
Impact resistant polymer construction provides light weight and resists operational abuse
Detent and spring pressure keeps sight erect but allows for unobstructed folding under impact, etc.
Compatible with most MIL-STD-1913 Picatinny / STANAG 4694-railed hand guards* and provides the same height-over-bore as standard A2 irons
Made in the USA.

SPECS

Position: Front
Height above rail, stowed: ~0.51 in.
Length, deployed: 1.5 in.
Length, stowed: 2.6 in.
Weight, w/ hardware: 1.2 oz.

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

*NOTE: Cannot be mounted to a railed gas block due to excess heat issues. Front MBUS must be mounted to a railed fore end on the same plane as the receiver rail. Because of this the sight is also not compatible with MOE Hand Guards.

See all of our AR15s and AR15 parts here.

Available options

Image	Description
	MBUS Front Sight Flip-Up Polymer for AR-15 Black UPC: 873750004310
	MBUS Front Sight Flip-Up Polymer for AR-15 FDE UPC: 873750004327
	MBUS Front Sight Flip-Up Polymer for AR-15 ODG UPC: 873750004334
	MBUS Front Sight Flip-Up Polymer for AR-15 Stealth Gray UPC: 873750011486

Please select a FFL Dealer

7 dealers near

No dealers found

Please search by another zipcode to find the nearest dealer.

Brownells Retail Store

You must select required check box

Note:

Listed hours & fees are not guaranteed and subject to change. Please contact the dealer to confirm current hours & fees.

* Must accept required fields.

Brownells Featured Dealers

Choosing a Brownells Featured Dealer is the fastest and easiest way to complete your purchase. Brownells Featured Dealers have agreed to perform FFL transfers on guns purchased online from Brownells. We have their necessary FFL information on file and your FFL order will ship directly to them once processed.
Standard Dealers

Standard Dealers have not yet agreed to perform FFL transfers on guns purchased online from Brownells. If you choose a Standard Dealer, you are responsible for contacting that dealer and arranging for the dealer to submit a signed copy of an FFL and to give Brownells permission to ship the gun.
Not Available Dealers

Not Available Dealers are dealers Brownells cannot ship guns to at this time. These dealers either do not meet our requirements for FFL transfers, or prefer to not perform transfers for guns purchased online from Brownells.

7 dealers near

Alternative products

Add on

MBUS® FLIP-UP FRONT SIGHT FOR AR-15 REVIEWS

4.6

7 Reviews

5 Stars

71%

4 Stars

14%

3 Stars

14%

2 Stars

1 Stars

Reviews Summary

The MBUS® Flip-Up Front Sight for AR-15 is praised for its affordability and ease of installation, making it suitable for casual shooting. However, some users feel it's not robust enough for rigorous use, highlighting concerns about its durability and adjustment mechanism. Overall, it's considered a decent budget option for less demanding applications.

What Reviewers Are Saying

Affordability and Value

67%

The product is frequently highlighted for its affordable price point, making it a popular choice for budget builds and casual shooting, with users appreciating the value it offers for the price.

Ease of Installation and Adjustment

60%

Many reviewers note the straightforward installation and ease of adjustment of the sights, contributing positively to user experience, especially for those who are not experienced with firearms.

Durability Concerns

50%

A recurring theme is uncertainty about the durability of the polymer sight under rough use. Reviewers indicate that while it may suffice for casual use, it may not withstand demanding environments or rigorous training.

Performance Limitations

40%

Several users mention performance drawbacks, particularly in terms of sight alignment and retention. Some felt that traditional designs offered better performance, indicating that the MBUS may fall short for serious shooters.

Casual Use Suitability

45%

The consensus is that while it may not be the best choice for heavy-duty applications, the MBUS sight serves well as a reliable backup or for those who primarily engage in casual shooting and plinking.

Sort by Filter by rating

Perfect fit!

Very much so needed for the build.

by DAVID RATCHFORD on August 14, 2025

Verified Purchase

Was this review helpful? 0

Very useful sight

I’ve built many rifle systems using this brand of sight. I am please with the ease of installation and adjustment it has. I’ll continue using these sights.

by RAYMOND FERNANDEZ on October 15, 2023

Verified Purchase

Was this review helpful? 0

MBUS gen2

Excellent value

by KENNETH CHAPMAN on September 16, 2023

Verified Purchase

Was this review helpful? 0

Solid quality

First time I purchased a polymer sight. This went on my 9mm ar9 pistol that I use just for range plinking. The polymer sight is of good quality, easy to mount, easy to adjust. The adjustment key is also polymer. BTW, a "steel" adjustment key will no work on this sight. So...don't lose the polymer key that is included. I don't know how "tough" the sight would be under a range "run 'n gun" type of shooting where the firearm would get a lot of bumping and banging against wood and\or metal objects. My guess is it would take a good beating, but again, it's polymer and not steel.

Nice Sight

Simple set up and easy to flip up or down for optics or storage. Easy to zero as well. Lightweight polymer is a plus too.

View All 7 Reviews

Customer Questions

0 Questions

MAGPUL - MBUS® FLIP-UP FRONT SIGHT FOR AR-15

Add To Favorite

Pin in Brownells Featured Dealers

Pin in Standard Dealers

Pin in Not Available Dealers

MBUS® FLIP-UP FRONT SIGHT FOR AR-15 REVIEWS

Brownells Featured Dealers

Standard Dealers

Not Available Dealers