Feyachi M40 3X Red Dot Magnifier with Flip to Side Mount, Focus Adjustment, Windage & Elevation Adjustable, 37/40MM Height

Compact and easy to mount variety of magnification with dial on eyelet top notch

Lines up well, crystal clear glass. Light enough that it doesn't make a difference in weight. Solid.

A good value for the money and it gets the job done at 25 yards. Easy to install.

It broke. Normal use, mounted on top of a 15 pic rail behind a red dot. I never even USED the flip out feature until last night (date is irrelevant, just noting review was written the next day), I flipped it out of the way to sight in some irons. Won't stay closed. Watch the video if you'd like, sorry it's dark. Next time, I'll go SIG or Vortex. Buy once cry once after all. EDIT: It's the next day. I took the magnifier apart and I figured out what happened. The pushbutton part has a rear face that the pushbutton shaft screws into (the one in the image above), holding & closing off all of the pieces within the tubular housing of the pic adapter. I removed that piece and noticed that there was a keyed slot on both the pushbutton shaft and the housing of the pic rail fastener. Lo-and-behold, the key was gone. If you look at the face of the rear piece I spoke of, it has two holes on it that happen to be the same diameter as the keyway slot. I think that plate loosened a bit and the key slipped through that hole somehow. I used a small piece of metal wire (10 or 11 mm long, don't know it's gauge, basically a hardened paperclip is what it reminded me of) and created a new, slightly larger diameter key. I filed it down until the rear plate could only rotate if I forced it forward after placing it through one of those holes on the plate. I tightened up the rear face and put one small drop (like, seriously, a tiny drop) of red Lok-Tite on the threads. Put it all back together and it works just fine again. Sucks this happened, but honestly, it's a solid magnifier when it's not broken! I have almost 3" of eye relief while I use it and it looks pretty clear. I'm sure a Vortex looks better, but this one fits the bill. Anyways, if that happens to you, just open it up and create a new key out of a paperclip or something similar. Works great.

This magnifier work great with the Sig Romeo5 optic.

Extremely blurry. Terrible eye relief

Works perfectly in back of my Sig Romeo red dot that I have on an AR pistol. I'm not sure why others had issues but on mine the red dot looked sharp and clear through the magnifier. It seems very sturdy. So far no issues using it at the range. Those others must have had astigmatism that makes the red dot splashy looking to the eye. That was then probably made worse using the magnifier.

Seems to be a good affordable optic. With the included spacer it lines up with the Strikefire II. I havn't measured the eye relief, but the 2.4 inches listed seems about right. It is a little heavier than expected, but i think that's probably a good thing for durability. Have not shot yet, but unless something crazy happens I'm pleased with the purchase.

Was surprised how well it works for the price. Solid, good quality with clear optics. Fairly heavy, but seems really well built.

I run this in conjunction with my Vortex Sparc AR and it looks great! awesome eye relief and a clear picture. Stands up to all the shooting and recoil just fine. Highly recommend!

Decent little product, solid construction, glass is clear, but it's definitely not a 3x. More like 1.5x. Calling it a 2x would be generous.

I Use it with Vortex Crossfire red dot. Works gret. However mounting bolt very easily gets loose. And it is 2x heavier then Vortex Micro 3x Magnifier. Adds quite a bit of weight, but it is 2 times cheaper...

Much better than expected. Easy to assemble, install, and zero. Provides plenty of eye relief, for me anyways. Can't go wrong at this price for something that's an exact clone of a name brand at 3-4x the cost. Glass is clear, hinge is secure, and a much better iteration than past 'M' versions. Can be used with red dot or etched reticles and the 3x is good to 100+ yards easily again, for me. Your results and eyes will be different than mine.