ACCU-SYNC Spring Loaded Flip-up Rear Sight

For the money, this is a great sight. The latching mechanism is a little stiff at first, but add a couple drops of oil and it'll wear in nicely. The adjustment clicks and aperture detent are tight and positive.The stacked design saves rail space, but can leave you short on scope clearance with lo-profile rings.Compared to the MBUS, these are quite heavy as they are all metal. Also, unlike the MBUS, they do lock in the raised position, so they won't fold if you run into a solid object. These are so tough, however, any impact hard enough to damage the sights would probably total the gun as well.Overall, pretty happy with the UTG BUS.

UTG is pretty much laughed at by “serious” shooters. I bought these for BACK UP as the BUIS implies. For that they are fine. Seem to lock up or down just fine. I like them better then the clunky looking MBUS. Plus they are half that price. So I got that going for me, which is nice.

Mounted these on a new AUG but ended up returning them because the folding design was too high to fit under my prism scope and needed to move the scope all the way back anyway for proper eye relief, but they're precision machined and the flip up feature worked flawlessly. I highly recommend if you have the room.

They were nice but didn't like the base where they attach, and a little expensive.

Imo, the best flip-up sights on the market. For the price you can't beat. Aluminum material, spring loaded activation button and don't take up much room. If you run a red dot magnifier this is the backup for you.

you better have thumbs of steel with these sights! i thought they were defective at first, nope, just unbelievably stiff. i have huge hands, drive truck for a living, use my hands and fingers more than average joe, and i thought i was going to break skin on my thumb getting these to work. it's a shame too because these fit snug on rail, look cool and seem rugged. maybe they loosen up after a 100 times deploying them, but as backup sights, i aint taking chance. these are going back tomorrow!

been waiting for this forever...finally got one. the small retaining screw is a bit of a pain to line up but the sight locks down tighter than the gold vault at Ft. Knox and the alignment is straight and true.it folds down neatly under my rifle's scope and even though it is a bit stiff but that's a whole lot better than a sight that flops around or pops up when you sneeze at it.

These are a great value. Much preferred over M brand