These seemed like your basic Glow in the dark bracelets. We bought one pack and still have not used them all. So far we have used about half and have not had one broken one. They shine pretty bright without a black light and of course are A LOT brighter under a black light. We did seem to have a little bit of a problem keeping them snapped in but if you make sure you break them completely at the ends they stay in there better. It is much cheaper when buying so many to get them here so I would definitely buy more.