I have a few bookshelf speakers and none of them fit both easily and securely. I had to drill holes in my speakers to mount them. The weight they claim to hold i think is really exaggerated since the speakers i mounted on them are 8.5 lbs and there is just no way they can handle double that. Sure you can get it to hold with your key hole mounts on the back of the speaker but that would limit movement and angles. I think the fact there seems to be little effort in making the mounting holes universal and the over stated weight rating is worth losing 2 stars. But if you can drill holes in your speakers and lock them onto the mounting plates the mounts do work well. Just make sure you dont go anywhere near their claimed weight limit.