It is a flat mirror, the addition of a little convex would be nice. I had to replace the aluminum button nut since i went down it snapped it. But the mirror was still ok. The only thing about the mirror is that it does reqire fairly often readjustment but from reviews i see that all of the ones that mount in this way do.
I purchased two of these to replace one that was damaged when my bike fell over.
This mirror becomes a necessity because without it I found myself continually looking for it on my bar end. Now I have a spare.
My last one of these mirrors had the glass portion fall out. This is a good mirror for the handlebars, but the vision is always limited by where it is aimed. I found that I much prefer a helmet or glasses mounted mirror.
I ride a lot in Atlanta traffic. I've pondered this mirror for years, and now I have no idea why I was suspicious. I guess because I never saw Miguel Indurain use one. This mirror weighs nothing, costs little, installs in seconds, and does not vibrate, so you can scan the road behind you with a quick glance. It takes about two seconds to appreciate it. It is especially nice because there are now many electric cars in the city.
I've purchased and installed several Third Eye Bar End Mirrors in the past, but these were installed on a tadpole trike and not intended to be used in the bar ends. I added a small piece of angle aluminum to each fender mount on the tadpole, took the mirror base apart and removed the bar end pieces, replaced the bolt with a shorter one with a Nylock nut, and attached the adjustable mirror head to the angle aluminum so that the mirrors are mounted directly over the front fenders. Worked out great. The mirrors look good and are out of the way. And of course they provide excellent rear vision which is really needed on a tadpole trike because it's very difficult to turn and look back in the form fitting seat.
I was most impressed with how little this mirror vibrates while riding. I'm not an engineer, but I think that's because there's almost no stem. Screwed tightly into handlebars, just like they said. Mine came with three different sized rubber expander sleeves, but not a lot of instructions, so it took a little experimenting to get it right.
Installed and went for a short ride to test it out. Could easily see traffic approaching from the rear; much better than my small helmet mounted mirror. Safety is becoming a bigger issue as it seems cyclists are having to avoid increasing numbers of inattentive/distracted drivers. This tool may save my life one day.
I bought this to try it out. I'm using this mirror at the end of the tube of a drop handlebar. I was able to find a position that is functional, but additional articulation would make this product more useful. Possibly it works better on other style handlebars; I haven't tried that yet. On another bike with a drop handlebar, I have an old-style Mirrycle through which the brake cable passes. I prefer the Mirrycle mirror.
It never occurred to me to have a mirror before I started riding to work 2-3 a week. Now, I can't see how I ever got by without it. I just adjust it however slightly is necessary to get a good rearside view. This allows me to know when vehicles are coming up from behind, but the real difference I've found is when I've got to execute left turns or merge to a left turn lane. One little awkward bit is that when I'm in the drops, the mirror is in the way of my wrist. But that is a minor inconvenience when compared to the overall benefits of having a clear view of what's behind at all times without craning my head around and losing visibility of what's ahead at the same time.
For the price it is a real good deal. I did have to shim it to make it fit in the dropbars I have . It works good I can see vehicles coming up from behind me better than I did with the other cheap mirror I had. Does take a little getting use to looking down but I can see what is behind me. Good price Good product.
I always feel safer riding with a mirror. In addition to viewing traffic behind me, I also get the benefit of not having to turn my head so often. This is the best mirror I have ever used!