When I developed these, one of my concerns was the possibility of warping on the larger swivels. I feel that this is the best way to go. These are one of the very few pieces that we make that aren't solid oak. But not to worry. There is very good quality here. Have you ever purchased a nice piece of office furniture and noticed that the staple holes aren't always filled. Doesn't look very nice, does it? On these swivels, they are all filled and stained. Most of the time you can't even find them. We start with a very nice 3/4 inch oak board for the top. Not particle board, but a high grade of plywood. Then we edge it with solid oak 3/4 inch thick and 1 1/2 inches wide. The overall height of the swivel is a little less than two inches. As you can see, the swivel movement is a high quality all steel base with ball bearings all the way around. This swivel base was selected for it's load bearing capabilities. It's rated at 1000 pounds. So even the biggest set won't be a problem. In addition, if your set is "front heavy", the base is easily moved closer to either edge to compensate.