These came off of an older RCA console TV set.  so it was fairly heavy and these allowed you to roll the TV on carpeting.   The wheel diameter is around 1.6" and the width is 0.6".   the console sat about a 1/2" off the ground.   These come with screws and clear brackets.  note theres is a few cracks around the a few of the holes, but these are still fully functional.   Theres plenty of different mounting holes as you can see.   they were mounted with 4 screws each and there are upto 8 holes.