need new batteries

[jeffreyace]

Using a sigelei 50watt box mod with aspire nautilus tank.
currently using imr 18650 3.7v 2000mah. No idea what brand as they don't say. I've been looking for vtc4s but I can't find any in stock anywhere. Would there be a different battery that would work nicely?
thank you

 

[wonner]

These should do very nicely:

Orbtronic SX30