Easy enough to assemble, got a new "gravel" bike with 28s and needed something to keep it vertical in the garage or basement and hold it while I clean. Works great, the top part has a moveable sliding piece that you simply slide down to the tire and it seems like a solid fit, I'm not worried about this at all it's very stable. The bottom "socket" for the tire has a thin cut for a thinner tire and a wider depression for a classic mountain bike tire, My 28 fits into the smaller notch just fine. If you have in between sizes I suppose it may rest on the wider portion and I don't think that would be a problem, does make me wonder why they bothered to put the notch in, I'm not sure it was necessary, but in any case I don't think it would be problem for other size tires, its working great for me totally happy with it.