This mirror is infinitely adjustable and fits on my sunglasses very securely. If your glasses have a semi-round temple, it might not fit yours. The mirror is distortion free so you can clearly see what or who is approaching from behind you. I like the mirror on my glasses so I can look around behind me by turning my head, something you can't do with bar-end mirrors. I've used these for years and saw an opportunity to get some extras at half-price while they were on sale so I can share them with new riders or others looking for a mirror.
I started using a mirror as a ride leader for a local cycling group so I could keep an eye on cyclists behind me. Once I got used to it which really didn't take long, I felt I was missing a critical piece of cycling gear whenever I rode without one.
The regular version may be a bit too close to the eyes for most people since it blocks a lot of your peripheral vision. I find the extended versions works better.
The mirror slides onto the eyeglass temple pieces. Some eyeglasses, particularly the fancier cycling eyewear, have oddly shaped temple pieces that may make it difficult to mount these, so take this into consideration.
In general, I found the eyeglass mounted mirrors to be more effective than helmet mounted or bike mounted mirrors. Helmet mounted mirrors inevitably get dislodged since they are generally attached with simple adhesive. Bike mounted mirrors tend to vibrate too much for my taste, and don't have a wide enough view to get the full picture of what is behind you.
Road biking. Helmet or eyeglass mirrors take a little while to get used to, but once you do, you'll feel hindered by the limited view of the bike mounted ones. Tried several others but kept coming back to this one for ease of adjustment and stability.
I tried this after a good review in Bicycling, but I'm not crazy about it. It is stable on my cycling glasses. But I find it difficult to adjust, not especially convenient to look into, and a tight enough fit on the fairly thick temples of my glasses that it changes their shape. Since getting this, I've tried a bar end mirror that I can adjust the angle on and flips up when not in use, and I find that works better for me. Still, the price on this is great and might be worth a try if glasses or helmet-mounted rearview mirrors work better for you.
I used to have a mirror on my Helmet and then I switched to the one that fits on the sun glasses and I cannot be happier. The Mirror is large enough to see traffic, moves with the head and does not obstruct. The only issue is it does not fold to go back in the case, which it was not designed for.
I would recommend this pair as a tool to see whowhat is behind you.
It attaches to my sunglasses and is angled for maximum and sufficient rearview. For several weeks I have used this item, the first of its kind that I have used. I have no complaints about it at all. I ride city streets with lots of motor traffic multiple times a week. No longer need I twist my neck around to see what is behind me. If you ride your bike where cars are driven, there is nothing to decide but to get this mirror.
Granted it looks a little dorky, but now that I have a mirror I don't feel complete if I am on my bike without one.
I prefer the head mounted mirror to the handle bar mounted variety, less vibration, easier to control field of view.
It is easy to mount on a visor, but not on a helmet with out a visor. Found an attachment device the works pretty well. Once mounted in a good location it is easy to a line the mirror for looking at approaching traffic. It is very light weight and good visual field.
Just got back from my first ride with this mirror. Wow. I've spent hundreds of dollars on fancy neon clothing, flashing lights, reflective fabrics... and nothing even comes close to the amount of safety that this tiny $XX device brings! Not only does it provide you, the cyclist, with information about cars behind you, but, for the first time in my four seasons of cycling, I felt like a valued vehicle on the road. There's an odd psychological behavior that I observed, and I'm not sure how to explain it, but if cars behind you know that you can see them behind you (you slightly tilting your head to view vehicles as they approach), they're much less likely to try something stupid (pass you with a semi-truck approaching in the other lane). Today, in my short 1-hour ride, I had three cars wait to pass me until the opposite lane was clear. No vehicle passed me with cars in the opposite lane. I even had people wait to pass me until no-passing lanes ended! It was amazing! I had more cars treat me like a vehicle in one ride than I have historically been treated in years! I'm not sure why mirrors have this effect and not flashing lights or certain clothes, but heck, for $XX... that's a steal. Stop reading and buy it. Your life is worth more than an IMAX movie.