They looked like what I wanted, but it was difficult to get an idea of their size from the product images. Now that I have them (I bought two) they are a little bigger than I expected which is actually very good! I've included some photos so others can see how they look and work (i.e. together, what can rotate, etc.). There are four main elements: 1. Main metal base 2. Plastic shell (a kind of lazy susan) 3. Spacers 4. Metal top that holds the monitor. Can be used with or without a gasket. Stand height without spacers is 2 inches (see photo). With padding, the height of the stand is approximately 3 3/8 inches (see photo). The top is about 11 3/4 inches wide. These are very durable coasters, both metal and plastic parts. In the photo that shows them on my desk, they each have a 27-inch Samsung curved monitor, which hopefully gives you a better idea of the size. The tray rotates freely and being slightly larger than I initially thought they can hold a lot more than I thought. The metal cover holding the monitor rotates but is fairly tight. The collar on the underside of the top metal piece slides over the top of the pad. So you have a plastic piece (clip) that fits snugly against another plastic piece (the plastic collar at the bottom of the top metal piece). It can be a little confusing but if you look at the pictures you will see what I mean. So the top piece of metal rotates, but tightly so it doesn't "spin" like a tray. . This is preferable for me as I want my monitors to stay in place. If you want them to spin more freely you can probably put a small amount of plastic safe oil/grease on them. If you twist them more, I'm sure they'll loosen up a bit. This is exactly what I was hoping for. I don't see any disadvantages so far.