They didn't come up so far on my calves. UCI legal I dunno - maybe a smidgeon too far up, but stayed there without the use of hairspray or glue stick. I have two pairs, one in white and one in black. They seem quite robust. Ideal for spring races. Maybe a tad warm later in the season. Great for keeping your feet warm in training (I would normally save this kind of product for races, but these are cheap and as mentioned pretty robust so have actually taken them to some club rides as well as solo rides). Highly recommended. I chose these over my Rule28 overshoes for a race last sunday ...