They are pretty useless unless you don't tow or tow something small like an open car trailer where you can see over the sides of the trailer. If you want to tow an enclosed trailer, forget about it.
What mirrors do you have on your truck? If you have the ones with a triangle, the holes don't match up. The power mirrors line up with the two mirrors mounts and it also needs a square hole for the bracket to side in.
Billy T.
[email protected]