I am laughing as I type this but I really do wish I still had that little vape pen. The cartridge system would be perfect for testing DIY vape juices. I found two clearomizers for the Ego-CC and two of those screw into the charger Ego batteries. I will use those if I can get any flavor from them. I still have a box full of the cartridges for the Ecab and I think that would be perfect for testing purposes. Oh well.........my Friday night thinking. 