The material is to flimsy. My husband even said my legs felt shaved 3 days later. Its full of speakers ok?The lights. I ordered an XL since Im very hippy size 14. And once broken in they will be super comfortable to wear for long periods. Dont expect some lifetime piece. There is no provision for standard 16" on center studs, either as 2 - 2 segments or 1 - 4 segment. not these. The closer to center of mass you clamp (front to back and top to bottom) the easier it will be to rotate the clamp arm if needed while the bike is mounted. My daughter does seem to have wider feet, so that may be the issue.