Fit System 3891 Deluxe Universal Clip-on Trailer Towing Mirror

I did not like the way this mirror mounted, didn't feel secure and interfered with the operation of the stock mirror. Once I had this mirror mounted it had forced the stock mirror into an odd angle and I couldn't adjust the mirror to an usable angle. As tight as I could get the straps (ratchets would start slipping at a certain point) vibration would cause the mirror to "walk off" the stock mirror due to the taper of the stock mirror. The mirror is convex (objects in mirror are closer than they appear) and I would perfer a flat mirror as I think the outer mirrors when towing are to see back behind the trailer, I adjust my stock mirrors when towing to see the blind spots next to me. I never went our on the road with these as I felt they would just fall off and I'd be out the $60 for the pair. I've sent them back to Amazon for a refund. If you've got these mirrors and like them pipe in here and let others know your experience.