Hi, we use this Starlights especially during night diving. When marking the entry and exit point make this really good services. The burn time is a few hours long enough (no dive lasts longer than the burn time of the lights). In addition, our instructors recommend always such a kick in the light Jacket / Leg pocket carry as an emergency light. So a glow stick is of course no substitute for a well-functioning Torche, can serve in a night dive in an emergency but to be able to at least read the instruments. I can really recommend these particles. And expensive are now being expected not. In particular, all divers wishes I "always good air"
