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.

These battery cases are nice for keeping my bartteries together and handy.

I cannot get the case closed. The flap will not fit over the part on the case that secures it closed. It looks like it is not made to fit at all.

Great product I have multiple of these cases Keeps everything organized. I keep them in multiple gear bags that may find themselves in austere environments.

This is an excellent battery case/battery holder for you 14500 (Unprotected) cells or your AA size batteries. I highly recommend them.