It's a 306 DCA (drip cup adapter) from GoodSense Vapor. There is a 306 atty inside...no leaking and adjustable draw. Only way to go for a 306 IMO.
I have heard that, of course I am not a dripper and wouldn't know. Ogre is and he is the only person I have heard of that doesn't like it. He never uses it and is thinking of selling it. I think he is just weird.......

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