Great quality, adjustability and fits true to size. They do run a bit smaller than other Yellow Box flip-flops! My daughter wears an 8 and I ordered the 8 1/2 - 9 1/2 and her feet fill up the entire shoe. Whatever material they are, I doubt they will ever wear out. The bonus 1GB of data was also a pleasant surprise! Had an issue with my gfs other headset, so we bought her these. They protect the bottom but not the top of the aero bars, which seems backwards to me. I?m not sure if this is an issue with Amazon processing or the confusing labels on the crocs (although Amazon should still have them sorted into the appropriate sizes for their inventory). I am always on my feet so its hard for me to find soft, light & comfortable sandals for the summer, let alone wearing it around the house. Had to return it.