Beware! The black rubber nibs on the tips of your nipple clamps can fall off, and, if lost, are not easily replaced! These nibs are similar to what you find at the end of the metal hook on a bungee cord. You can imagine the bite of the metal clamp on your nipple, should you lose one!
To keep your nibs from wandering astray, take them off when you first get your nipple clamps and dab a bit of clear nail polish or a craft glue inside the nibs, then put them back on to the tips of your clamps … this will help hold them in place for the long term.