What's important about a battery case, anyway? Well, it needs to hold the cells securely so whether there's just one or it's full, there's no rattling about... And it needs to close securely, so it doesn't open while in your pack or case or luggage... And it needs to open reasonably easily despite closing securely... And it needs to be cheap, to boot. The Tenergy 4 AAA case actually does all these, although the "opening reasonably easily" can be a bit of a challenge if you have weak or arthritic hands. I'd be careful when opening the case if it has been left out in the cold; let it warm up a bit before trying to force the tab down to pop free the mating clasp. The Tenergy 4 AAA case is a "scaled down" version of their 4 AA case. Some might use the AA case for both AA's and AAA's if extras for both are needed.

Useful for the storage of loose batteries. I have had these plastic cases for a few years now and not one of them has failed yet.

I like to keep all my batteries in plastic cases for safety reasons. These cases work great and are clear so you can see what type they are.

Great for organization and traveling.

We use these to safely hold the lithium batteries for the "emergency" flashlights in our vehicles. When needed we don't have to fumble/fight with packaging. By keeping the batteries separate, if the happen to leak it will not destroy the flashlight. With the number of flashlights that take 3 AAA batteries, I would appreciate a model that holds 3 batteries.