Now that is a new one. Never saw a rim labeled like that. Not sure why the have it labeled like that. I would have no qualms whatsoever about putting a 700x28c or even a 700x32c on that rim though.

The *only* thing I can imagine is that maybe the frame that the wheelset originally lived with was restricted to that size tire. I have one bike that will ONLY take 700x23c or smaller. Maybe a 700x25c but haven't tried that but I have tried a 700x28c and the curved seat tube totally rubs on the tire badly.

So maybe the wheelset was put on a bike frame that could only handle those skinnier tires and the bike company wanted those stickers put on those rims to let people know to buy only those sized tires when replacing them. Shrug. I dunno.