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MAGPUL
AR-15 MBUS GEN 2 TACTICAL REAR SIGHT

873750004358 100006787

Description
Ratings (9)

Low-profile, flattop-mounted, polymer sights deploy instantly at the touch of a finger to provide backup sighting if a primary optic fails. Streamlined contours mean there’s nothing to snag on brush, sling, or other gear when folded. Spring-loaded ambidextrous release mechanism lets you hit the grooved tab on either side of the sight to deploy, and lock it in place. Hitting the same tabs retract the sight when you’re done. Uses less than 1" of MIL-STD 1913 Picatinny receiver rail space and locks securely in place with the included steel crossbolt. Provides the same height over bore as standard A2 iron sights. Windage-adjustable rear sight has two apertures: a large, .185" peep and a .070" peep. Designed for AR-type rifles and carbines, fits any weapon with Picatinny rails.

Reinforced, injection-molded polymer, Black, Dark Earth, or O.D. Green. Heights measured from top of rail to top of sight. Rear Sight - 1.5” (3.8cm) long deployed, 2.6” (6.8cm) long folded, 1.2” (3cm) wide, .5” (1.3cm) high folded, 1.6” (4cm) high extended. Large aperture, .185” (4.7mm) diameter. Small aperture, .070” (1.8mm) dia.

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Customer ratings for MAGPUL MBUS REAR SIGHT FLIP-UP POLYMER FOR AR-15 BLACK

Number of ratings: 9
From brownells.com: 9
Average rating: 3.6

MBUS GEN 2 REAR OD GREEN by MAGPUL (01/07/2011)

I use this on my 9mm AR low profile nice look and works as advertised a bit tight with the changing of the sight aperture and sighting in but works none the less.

Best tactical color BUIS (23/02/2013)

OD green is my favourite color in tactical type firearms. Black guns is more common while OD green is more stunning with tactical type rifles when coordinated properly with matching furniture. Magpul's MBUS is an excellent alternative to metal BUIS at the fraction of the price. However, care must be observe not to excert excessive force when tightening the assembly screw as it will crack the plastic material. The supplied front adjustment tool makes sight adjustment a breeze. Great design, easy to install and higly functional.

Decent Value, So-So Design (11/03/2016)

Technically speaking, there's nothing to complain about with the MBUS; they're easy to install, they zero simply enough, and the fast and flexible deployment options (just press the center or either of the side flanges) are a welcome feature. However, the idea of sights is to allow reasonably fast and accurate aiming in the field, and a couple of areas of the MBUS design don't lend themselves all that well to this purpose. Specific to the rear sight is the square profile of its "ring" - the holes are round, but the pieces into which they're drilled are square. While this may seem immaterial, in practice the shape clashes with the roundness of the hole, doesn't do as much to draw in the eye, and, thanks to the extra material at the corners, blocks more of the space around the target. For me, this makes aiming slower and clumsier at defensive ranges, at least when using the more accurate narrow aperture. The flip-up piece used to change aperture size isn't quite as fast as a traditional rotating head, though it does help minimize the sight's flipped-down profile for those who use large-lens optics. And this particular color (FDE) was found to reflect more light into the eye from the posts flanking the aperture, and this sometimes added to the element of distraction (although the contrast did help isolate the black center piece, so I guess it's a trade-off). So if you really just want an affordable but decent-quality backup unit, you could do a lot worse. But if your irons are more than just a last-ditch measure, I'll suggest springing for a nicer set.

Mmmmmmm.... bear claws! (24/03/2011)

I have both the original MBUS and the Gen 2 MBUS installed on my rifles and they are both reliable well made sights. While the Gen 2 is a bit lower profile and the retaining nut casing is a tad thicker, I really don't see a huge difference in the two products. For the money, a great BUS, I just don't see what all of the hoopla and the suspense was about. Well worth the money, though.

The real deal (02/06/2011)

These sights are as tough as nails without adding extra weight. With all of the extra equipment on my M4, weight is an issue for extended periods of use. It is nice to add quality equipment with no change in weight, and the MBUS work great and stay out of the way until you need them. A must have if you have an M4.

Be Aware (02/02/2012)

This sight will NOT co-witness with a standard A2 front sight. If you have a Bushmaster Dissapator type rifle, look elsewere. I still haven't found a rear sight that will line up correctly with a permanent front sight.
Good quality sight but needs an adapter to raise it up to the correct level.

I would by it again (04/03/2012)

Mounted this on my AR build and have had no problems. I only rated it 4 stars because the peep sight could be smaller for the long range shooting. Overall though very satisfied and will purchase again for my next build. Brownells has fast shipping to, withing three days I had my sight.

Okay but flimsy (30/01/2013)

This would probably hold up for a use or two, but the materials and the workmanship were , well, sort of flimsy, flexible and not confidence inspiring. For a very limited, occasional use product it might be okay, but for anything serious, it just won't make a person feel like it'll last or work. I returned this item.

Decent but not great (03/04/2013)

I'm a big fan of Magpul hardware, but this fold-down backup sight was a little underwhelming. It does not seem as sturdy as I would have liked. It is functional and works as advertised but I have reservations about the long-term usability of this item and whether or not it will stay in one piece and hold zero over the long term. It was very difficult to flip down the front peep aperture, so much that I almost broke it. I know Magpul's area of expertise is quality injection molded plastics, but sadly I have come to the conclusion that there is no substitute for quality all-metal sights.

Read 9 more ratings on brownells.com

64.9 64.9 4 GBP

Product no.: 100006787
MAGPUL MBUS REAR SIGHT FLIP-UP POLYMER FOR AR-15 BLACK
Mfr Part: MAG248-BLK 873750004358 Low-profile, flattop-mounted, polymer sights deploy instantly at the touch of a finger to provide backup sighting if a primary optic fails. Streamlined contours mean there’s nothing to snag on brush, sling, or other gear when folded. Spring-loaded ambidextrous release mechanism lets you hit the grooved tab on either side of the sight to deploy, and lock it in place. Hitting the same tabs retract the sight when you’re done. Uses less than 1" of MIL-STD 1913 Picatinny receiver rail space and locks securely in place with the included steel crossbolt. Provides the same height over bore as standard A2 iron sights. Windage-adjustable rear sight has two apertures: a large, .185" peep and a .070" peep. Designed for AR-type rifles and carbines, fits any weapon with Picatinny rails.

64.9 GBP 942 £64.90 *

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Specs: Color: Black Make: AR-15 Style: Flip-Up

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Top takeaways

The AR-15 MBUS Gen 2 Tactical Rear Sight is a low-profile, polymer backup sight that mounts on a flattop and deploys instantly with a touch.
It features a spring-loaded ambidextrous release mechanism, uses less than 1" of Picatinny rail space, and is windage-adjustable with two aperture sizes.
Compatible with AR-type rifles and any weapon with Picatinny rails, it offers the same height over bore as standard A2 iron sights.

Attributes

Colour: Black Make: AR-15 Style: Flip-Up Delivery weight: 0.054kg Shipping height: 25mm Shipping width: 102mm Shipping length: 165mm UPC : 873750004358

Item details

Made in USA

Product no.: 100006788
MAGPUL MBUS REAR SIGHT FLIP-UP POLYMER FOR AR-15 FDE
Mfr Part: MAG248-FDE 873750004365 Low-profile, flattop-mounted, polymer sights deploy instantly at the touch of a finger to provide backup sighting if a primary optic fails. Streamlined contours mean there’s nothing to snag on brush, sling, or other gear when folded. Spring-loaded ambidextrous release mechanism lets you hit the grooved tab on either side of the sight to deploy, and lock it in place. Hitting the same tabs retract the sight when you’re done. Uses less than 1" of MIL-STD 1913 Picatinny receiver rail space and locks securely in place with the included steel crossbolt. Provides the same height over bore as standard A2 iron sights. Windage-adjustable rear sight has two apertures: a large, .185" peep and a .070" peep. Designed for AR-type rifles and carbines, fits any weapon with Picatinny rails.

64.9 GBP 159 £64.90 *

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Specs: Color: Dark Earth Make: AR-15 Style: Flip-Up

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Product no.: 100006789
MAGPUL MBUS REAR SIGHT FLIP-UP POLYMER FOR AR-15 ODG
Mfr Part: MAG248-ODG 873750004372 Low-profile, flattop-mounted, polymer sights deploy instantly at the touch of a finger to provide backup sighting if a primary optic fails. Streamlined contours mean there’s nothing to snag on brush, sling, or other gear when folded. Spring-loaded ambidextrous release mechanism lets you hit the grooved tab on either side of the sight to deploy, and lock it in place. Hitting the same tabs retract the sight when you’re done. Uses less than 1" of MIL-STD 1913 Picatinny receiver rail space and locks securely in place with the included steel crossbolt. Provides the same height over bore as standard A2 iron sights. Windage-adjustable rear sight has two apertures: a large, .185" peep and a .070" peep. Designed for AR-type rifles and carbines, fits any weapon with Picatinny rails.

64.9 GBP 198 £64.90 *

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Specs: Color: O.D. Green Make: AR-15 Style: Flip-Up

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Product no.: 100014406
MAGPUL MBUS REAR SIGHT FLIP-UP POLYMER FOR AR-15 STEALTH GRAY
Mfr Part: MAG248-GRY 873750011493 Low-profile, flattop-mounted, polymer sights deploy instantly at the touch of a finger to provide backup sighting if a primary optic fails. Streamlined contours mean there’s nothing to snag on brush, sling, or other gear when folded. Spring-loaded ambidextrous release mechanism lets you hit the grooved tab on either side of the sight to deploy, and lock it in place. Hitting the same tabs retract the sight when you’re done. Uses less than 1" of MIL-STD 1913 Picatinny receiver rail space and locks securely in place with the included steel crossbolt. Provides the same height over bore as standard A2 iron sights. Windage-adjustable rear sight has two apertures: a large, .185" peep and a .070" peep. Designed for AR-type rifles and carbines, fits any weapon with Picatinny rails.

64.9 GBP 519 £64.90 *

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Specs: Color: Gray Make: AR-15 Style: Flip-Up

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Upgrade your AR-15 with the MAGPUL MBUS GEN 2 Tactical Rear Sight! ✨ Low-profile, instant deployment, and windage-adjustable for precision.

Description
Ratings (9)

More...

Customer ratings for MAGPUL MBUS REAR SIGHT FLIP-UP POLYMER FOR AR-15 BLACK

Number of ratings: 9
From brownells.com: 9
Average rating: 3.6

MBUS GEN 2 REAR OD GREEN by MAGPUL (01/07/2011)

I use this on my 9mm AR low profile nice look and works as advertised a bit tight with the changing of the sight aperture and sighting in but works none the less.

Best tactical color BUIS (23/02/2013)