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Magpul MBUS Gen 2 Flip-Up Rear Sight AR-15 Picatinny Compatible Injection Molded Polymer Black

Typically ships the same business day when ordered before 4pm CST.
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Magpul makes high quality injection molded parts and accessories, primarily for the AR15 rifle platform, right here in the USA. Polymer backup sights are popular for several reasons, including low weight, quiet operation, and durability. High quality polymer can take a certain amount of abuse without breaking, and still return to its original form, unlike metal, which may permanently deform, or even break.

Specifications and Features:
Magpul MBUS Gen 2 Flip Up Rear Sight MAG248-BLK
Injection Molded Folding Back Up Sight
Impact resistant polymer construction provides light weight and resists operational abuse
Spring-loaded flip up sight easily activated from either side or by pressing the top
Detent and spring pressure keeps sight erect but allows for unobstructed folding under impact, etc.
Clamps to MIL-STD-1913 Picatinny/STANAG 4694 receiver rail and provides the same height-over-bore as standard A2 irons
Protective wings shield the dual, same plane flip apertures
Sight can still be folded with either large or small aperture in position
Detent knob easily and positively adjusts Windage
Made in the USA
Overall Weight 1.3oz
Overall Height Stowed .51"
Overall Length Stowed 2.6"
Center of Aperture to top of rail 1.42"

AR-15, AR-10, DPMS-LR308 and similar pattern variants
Note: The dual aperture MBUS Rear Sight is adjustable for windage and fits most 1913 Picatinny rail equipped weapons, but is specifically tailored to the AR15/M16 platform


Item#: ARR-850
Total number of Reviews: 17

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4.0 5
"This is a great back up sight. The peep holes don't seem quite as nice as your standard AR15 rear sight. Over all I like this one better than the front sight."
5.0 5
"This is an awesome site! fully adjustable and folds down out of the way for other optics.. MagPul makes some of the best AR assesories I have ever used. Worth the money!!!!"
5.0 5
"When I ordered this sight I was a little weary about what the quality was going to be like with that low of a price. Needless to say I am very happy with the sight. It looks great and serves it's purpose."
4.0 5
"Nice quality BUS. Only challenge is that it is rather long and bulky when in the collapsed position. I have the Magpul MBUS front sight installed on my S&W MP15 along with a Eotech holo sight. I had to mount this rear sight on the very last section of my flattop rail, where it's overlapping the charging handle. Makes it really tough to turn my Eotech on/off and makes cycling the action difficult."
5.0 5
"This is an awesome sight! I am very very happy with it! It feels very solid and is light weight !! I would recomend this to anyone who is looking for a rear flip up!!! Now I just wish they would make one OD green!!"
3.0 5
"This appears to be an ok BUIS. I have a friend that has one, and I thought I would give it a try. I ordered mine and was dissapointed when it arrived without the bolt that attaches it to the rail. Um... thats kinda important... lol. not to worry, CTD was willing to make it right (thanks CTD) but I decided to just go to the local hardware store and get a bolt/nut that fit. Its installed now, seems secure and looks good on the gun, functions well, althought I have not had a chance to sight it in however it works wonderfully with my Eotech. Nice height to see through the lenze clearly and great co wittness ability so far. May update after shooting.... but should be fine for what its intended for, not everyday use, \"just in case\" there becomes an issue with the eotech."
4.0 5
"For the price, it can't be beat. Very happy, but not perfect."
3.0 5
"I loved this sight until I got it to the range. I dont like the small peep sight. I didnt think it was as crisp as an A2 iron. made very well other wise. I replaced it with a UTG buis and wouldnt go back for anything. Also everthing on my rifle is magpul>"
5.0 5
"Aperture holes are a tad small, and the price for rear sights is always overpriced (With EVERY rear sight). Works just as it should. Quite happy with it. Mounted on my Draco SBR."
5.0 5
"I was leary of a plastic part at first,but this turns out to be a great back up. it's solidly built, zeroed easily and I personally like the small aperture (if you're up close and personal just flip down the small one and you can take a very quick shot)."
5.0 5
"The shipping was fast and easy, and I received exactly what I ordered. I ordered a front sight from another company the same day I ordered this and I am still waiting for it. Next time I will order everything from CTD even if it is a couple bucks more.Nice rear rear sight, but the smaller aperture hole is a little too small, but nice for the price. I have not used it at the range yet."
5.0 5
"Got exactly what was advertised. Works great on my DPMS and was $60 cheaper than what my local gun shop wanted."
5.0 5
"When I first got my hands on this sight, I thought it was a cheap piece of plastic, but to my surprise it is a stout peep. They should add in the directions that you can fold down the small hole sight for the large sight. I will buy again."
5.0 5
"As for those complaining about the aperture being small, the smaller it is, the more precise it is. All in all, great and sturdy sight."
4.0 5
"The day aperture seems small. Sure, the smaller they are, the more accurate you can be, but I had a hard time focusing due to the small size. The large size of the front post didn't help. I think if I replaced the front sight post, I might like it better. I have a KNS Precision Item # 2-KNSSIGHTPAK front sight on my AR and love it. Not sure if those would replace the front sight post or not. These sights I actually bought for a friend's B-Day. He likes them as back ups, which is what he uses them as, but wouldn't use them as primary. They aren't accurate beyond 100 yards. The front sight is too big and the back is too small. They were the standard carbine distance apart from each other. I'd buy again if I knew I could change out the front sight post. But I'd be more likely to buy a higher quality folding sight that costs more."
5.0 5
"Very nice site. Very sturdy and well made."
3.0 5
"Per Magpul "These rear sights will only function with the higher "F" marked A2 fixed front sight or Magpul front sight." They will not work with "standard" A2 fixed front sights - I asked them prior to my purchase and was told yes, but after installation when they didn't work correctly I again contacted Magpul and was told, "sorry they won't work with the non-F marked fixed A2 front sights." I needed to install an extra tall front sight post to make these work."