Review on Enhance Vehicle Safety with Utopicar's Adjustable or Fixed Blind Spot Mirrors - Wide Angle Rear View Mirrors for Cars [Frameless Design] (2 pack) by Don Leblanc

This mirror is naturally curved for a better view, making it difficult to attach to flat glass. The mirrors already had 3M foam tape that was not positioned all the way to the edge, so not a well sealed contact point with the car mirror. There were also about 10 round round reversing taps from 3M that could be stacked on top of each other so that the center of the mirror touched the car mirror. A large gap allows water and air to circulate between the car mirror and the small auxiliary mirror. There are also a few plastic adapters that you can use to connect the mirror to the car mirror that pivot and protrude farther than the straight bar on the car mirror. If you purchase this product, you can also purchase the 3M waterproof tape as the tape that comes with it is not considered waterproof. The waterproof tape is an adhesive tape with a red peel-off backing. I suggest that the manufacturer install this mirror on a plastic base that is molded to match the size of the front of the mirror and has a flat back so the tape doesn't get much exposure to water, and use 3M waterproof tape. That will increase the price, but in the long run it will be very insignificant.