Gorilla Glass only offers round ends now.
** The clear crystal color is made from borosilicate glass and all the other colors are made from soda-lime glass. **
Approx 9/16" to 5/8" diameter
All captives have rubber beads for easy use. The beads can vary in hardness, some will be every soft and some will be harder. It depends on what Gorilla Glass has onhand.
For in-between sizes, crystal is no longer available. Those sizes are 7g, 5g or 3g. If you still pick crystal for those sizes, it will automatically come as black.