Take-A-Look Cyclist Mirror
If you want to use a mirror on your eyeglasses, the Take-A-Look Mirror is what you need. They can be adjusted so you can look into the mirror without straining your eye. Take-A-Look mirror features three pivot points for multi-adjustments and the perfect fit. Provides optimal viewing with wide field of vision. Durable stainless steel and brass frame with an optically correct acrylic mirror.
As far as helmet/glasses mirrors go, this is the undisputed king. Once properly installed, it's not going anywhere. That being said, having a tiny little mirror sitting up there in my peripherals is maddening and the mirror isn't quite big enough to really give you a one-look sense of what's coming. If you're into helmet mounted stuff then this is the best. If you're not sure, then you're probably not and would be better served with a handlebar kit.
I've tried various handlebar-mounted and sunglass-mounted mirrors. This one is the best. I've used it for probably 5 years so far, it hasn't broken, and my guess is that it saved my tail more than once.
This is great mirror, I bought it though vs another because it was made in the USA. The mirror clips onto you sunglasses and stays put without coming loose. Because the mirror is so close to your eye the small mirror makes a fairly large image area of view behind you yet it doesn't compromise your forward viewing area. It has many angle adjustments for it so you can find the right angle no matter what. This was the first mirror I ever bought and now I don't ride without it, however, just as I do in my car, I don't rely on the mirror, I use the mirror to get an ideal of what's going on but I still crank my neck to make a double check of whats behind me when I need to make a lane change etc. I've had it for a year now and it still is holding up just fine so I think it's very durable.
I've tried several cyclist mirrors out, including those mounted on the bike and helmet and this mirror has been the best by far. It provides for easy mounting to the arm of your glasses (the best type of arms are those which are flat) and easy adjustments. The view for whats coming up on you from behind is excellent, clear and easy to focus on. A cyclist riding any road which is travelled by other vehicles should not be riding without a way of knowing what's behind and this is one product that will serve you well. I'd recommend this mirror to all my cycling friends