Designed from the ground up with Boge cartos in mind. There are a lot of features so let's start from the top:
Threaded stainless steel top cap with a filler screw. An 18ga needle just barely fits in here, we recommend a smaller needle for filling through the hole. However... it's mostly redundant since you can just unscrew the cap like a vivi nova and drip in to fill it up!
Threaded Poly tanks, yes, tanks. It comes with a shorty for standard size cartos and a longer tank for the Boge XLs and DC style cartos. Fat cartos will not fit, but between the two tanks, any standard or long carto will.
It also comes with an adapter. Your carto seats into the bottom of the tank, it does not go all the way through, the threads stick out into the kilt and you screw on the adapter to lock the carto in place. This tank is stuck at this point, you can't pull it up or push it down so no more laps full of juice because you picked your device up wrong or the tank decided to be slippery that day! The threads on the bottom of the adapter stick out far enough to give you air flow on just about any device.