On first glance, this is a clever looking foldaway design. Unfortunately, they're useless at any speed over 25mph as the mirror vibrates and moves out of place no matter how tightly you screw the clamp down.
I'm not impressed with this mirror. It mounts poorly and shakes a lot. I bought this just to get my WR450 street legal. I would not recommend this for anything else. It moves quite a bit and you can't see anything while riding. Most of the time, I have this tied up out of the way while riding offroad.