Originally I bought this power station as a battery backup, but a friend of mine in a google hangout turned it into an e-cig with just a USB to 510 regulartor you can buy online.
What you need:
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There are 2 USB connectors on the powerbox. You are supposed to use the one above the power button. The USB to 510 connector has adjustable voltage up to 4.8v
POWER BOX: HERE
BATTERIES: HERE
TOTAL COST: $37.09