As the vaping industry advances, and we put more and more energy into our 18650 batteries, it becomes more and more important to keep your batteries in a case. You wouldn't even want a AA rattling around in your pocket and shorting out: an 18650 contains substantially more energy! So #vapesafe and always carry your batteries in a case like this excellent Storacell Quad-18650 Battery Case. Bright orange so you'll never miss it, the Storacell Quad-18650 Battery Case carries four cells securely: they slide in with ease, but lock in place so they won't fall out. Releasing is as easy as sliding the battery out. In addition to protecting the battery from accidental shorts, it also protects the insulating sleeve of the battery from incidental damage.
You wouldn't keep lightning in your pocket: keep your batteries safe in a case!
Do we need to say it? Yes we do: batteries not included!