If the carts that come with your 510 are pre-filled, you'll have to wash them out (after
vaping the contents), if they are empties/blanks, just fill 'em up.
Any 510 cart can be re-filled with any e-
juice that you like, just give the filling a rinse if you don't want any flavour cross-contamination.
Check out moobyghosts youtube channel for tips and tricks...
YouTube - Mooby's Guide for Noobies: How to Refill Carts
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