I have been using a 650 mah ego passthru, and am looking to get some replacement batteries. I got unexpectedly upgraded to tank atomizer I am pretty sure type A, not sure the capacity of the tank but it seems to be only a little over a Ml. The tank has one of those silicone caps on it, and it has leaked but with some of the tips here I think I can handle that by ordering some replacement caps and using the 12 ga needle trick. Any recommendations on an upgrade battery I should be looking to? I like the look of the clearomizers, and I like the tank for holding liquid, seems very efficient. I want to try a variable voltage battery, but I definitely want to stay with a passthru that is also a battery. I like the ones with the locking feature(5 clicks) Any suggestions from the wisdom of the forum? I have not kept up with innovations in the past year and am open to just about any suggestion. I am curious about the new attys that you just replace the head on? Anyway, any help would be greatly appreciated.