I use the screw fill hole it comes with, I'm pretty sure it's the v2, the thing works great all day when on my box mod sitting up right but if it ever goes sideways for more than 5 minutes it leaks all over my mod and scares me because it's the BAP DNA40 and I don't wanna fry it or anything. It seems like when the juice channel gets exposed to air it loses pressure? Idk if that's right I just can't figure out what else it could be and seems like if that's the case more people would have similar issues but I appear to be the only one lol. Thanks for the reply, I'll see if I do that on my next fill up.