They are nicely built and look great. Only problem is there is no way to keep them in place without modification. I finally resorted to buying a couple of round velcro adhesive pads to secure them. This worked for me, since they can then be removed when not in use.
For $20 one would think that this manufacturer would have spent more time on functionality than asthetics. Save your money and make your own from items one can get at any hardware store, unless you are into looks only and not functionality.