UTGSuper Slim Flip-up Rear Sight

Impressed, and this is comparing it to my MBUS polymer, and the cheap but equally effective GRG back up iron sights I also got off Amazon. Thousands of rounds on the GRG's, and all they required was a small teardown and blue loctiting, and they have been rock solid ever since. Don't care for the aperture setup on the MBUS polymers at all.These are not spring loaded, but they do stay down, and when you flip them up manually, they click into their upright position with ease. They snap up, and the locking detent pops out and locks them upright. The aperture setup on these sights is why I migrated back to these from any other back up iron sight; look closely at the pictures on Amazon and you'll see that's it's a neat design.Sight picture is great, but using these apertures is a bit different than your traditional M16A2 sight picture. The apertures are almost invisible, kind of ghostly in your sight picture. Just enough of it can be seen to get your sights lined up, but this also allows for far more peripheral sight picture awareness.Attached is my final 3 shot group, from the range today, after three 3-shot groups to re-zero my rifle. I did NOT need to adjust any windage in, and that was the case with the first set of these I've had in the past, which is odd, in a cool way. My rifle had been re-assembled after my doing some work on it, so I was re-zeroing the entire system, not just the sight. Dialed in to this level after 12 rounds and the rifle as a whole running 100% is awesome; my front sight post on my rifle needed the adjusting. Still a touch high, but excellent for my purposes. Rifle was still a bit dirty in these photos.Results speak for themselves. In terms of durability, these seem quite tough. I'm not worried about the flip up detent ball being polymer, as you're not going to be actuating the sights 8,000 times a year. They're back up sights, not flip them up and down every other shot, sights.I purchased this unit back in the end of 2016, but returned it after a couple weeks due to the little detent switch not quite working. It seems as though that has been fixed entirely. There seems to be an added steel plate where the locking switch rides inside the sight mount, which the old unit didn't have IIRC.Buy them. I'm using these over more expensive sights. BTW, these are the rear sights that come on the Saint rifle, from you know who. I can't think of a reason to not rate it all at 5 stars; easy as pie to install, $21 is amazing for a decent rear sight like this, and the accuracy is excellent.

2nd Edit: I've had these sights for a couple months and even originally thought I'd replace them the Magpul MBus. But the longer I have them the more I like them. It's been cold so no outdoor shooting and I finally got to a range with a 75 foot lane. I was pleasantly surprised that the grouping of these iron sights was as tight as my red dot, and the iron sights tell me that I have to re-zero the red dot. No bench rest in these two groups shown in the last image above.Edit: As a new rifle shooter I didn't understand what "lower 3rd co-witnessing" was. I thought I needed sights that stood up more and also didn't understand that I wasn't holding the butt stock of my rifle high enough. And so I may repeat some of what I said initially, but have grown to have a greater respect for these sights. As I've lived with them for a few weeks I can say they are very easy to install, to use and sight in, providing you get a front sight adjustment tool. If anything fails it will be the ball bearing that allows the sights to flip up and hold position. While they do not have the push button flipper that Magpuls have, they can be deployed just as quickly. Unlike Magpuls you don't have to wrestle them on and they secure easily and lay very flat.I have changed my rating to 5 stars.If you're a range warrior like me these should suffice. Most of us aren't spending 6 months in Iraq pr Afghanistan, toting these things around, dragging them through sand on a daily basis. You can always spend twice the money or more for something more "battle tested" but I think that choice would be made for durability in harsh conditions rather than because of ease of use or accuracy. I think these are reliable enough as they seem well engineered and manufactured to withstand a modest amount of abuse.This rear sight installed in seconds on my picatinny rail. My only (remaining) question is how far back is optimal? I have room to move backwards, but want to make sure that when folded is clear of the charging handle of my AR.It is simple to operate. Just flip it up and it locks in place. You push the release button and fold it back, all done with one hand. It's got two apertures, a wide and narrow which you can alternate with a simple flick. The windage adjustment works as advertised, with nice little "clicks" as you make your adjustments.I found these to be great in the respect that I don't have to dismount my red dot to use the iron sights. Even better, I was able to use the red dot to be able to get this rear (and also front) sight align and basically sighted in. If this works for the initial adjustments it should save me some $$ not having to spend it on ammo to get it sigthed in. I'll have to see how good this method works later in the week at the range. [See edit below].Edit: I gave it overall 4 stars and probably would have given it 4.5 stars were that available. I don't think these are rugged enough to withstand 6 months of daily abuse in Afghanistan, but most of us aren't in Afghanistan or Iraq, are we? I did get out to the range to test them, and was got them zeroed in quite nicely, I think. My AR is my first rifle so I didn't understand things like "lower third co-witnessing" and initially thought the rear sight didn't stand up high enough. Maybe compared to others it doesn't, but it seems good enough for a backup and the quality for the $50 or so I spent on the set I think they are quite well made. The windage adjustment worked easily but getting the front sight lowered without a front sight adjustment tool was an ordeal. I subsequently got this one [https://www.amazon.com/gp/product/B00IOF60LQ/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1] and made things a lot easier. The only thing was that I had to screw the front sight down as far as it could go to zero, using the co-witness of my red dot to zero in, which worked quite well [see target photo- 65'/20 meters, no bench]. I got to compare them with a set of Chinese Magpul knockoffs and these are FAR superior- and for not that much more money.

Fit great and is made of good material. Price is good and installation was easy.

Haven't shot with it but I can tell you that flipping up and folding down the sights was pretty stiff. I don't mind that it's hard to flip up the sights since i wouldn't want it to accidentally snag and flip up the sights. The profile pretty slick and seems like a quality piece. My only concern is that the ball that applies the friction to prevent the sight from flipping or folding easily is that the ball is polymer that's constantly rubbing against the aluminum (not that you should continuously fold and flip the sights), but I'm assuming that the ball will wear out.Update 1/12/17:Took it out on a few trips and I can only complain that the rings kinda fade out a lot compared to the magpul mbus pro or even the A2 rings.Used it along with the front sight counterpart (the low profile flip up front sight that goes along with this rear sight, sold seperately in my case).Other than that, it works, it's slick, and probably the best budget lowpro iron sights you can get. Heck I'd say it's better than the polymer magpul mbus

Works grea. Very durable. PLEASE NOTE THAT THIS IS NOT SPRING LOADED. You must manually flip it up, but it lock in place very securely once up. Worth a buy.

I truly believe you can’t go wrong with iron sights. Better the have and not use than to not have when needed. Works really well it was super easy to install fit great and the alignment was perfect and the design was nice touch metal is way better than plastic. The weight is unnoticeable and and the brightness is good depending on time of day.