I was looking at those carts initially too, but when attached to the blue battery they're too tall to close the PCC. I went with a v-nano clearo instead. That doesn't fit either but I keep one completed clearo/battery in my pocket (usually just put a silicone cover on the tip since it'll be in my pocket most the time) and in the completed slot of the PCC I carry a extra clearo filled with another flavor (i use the lil silicone cover from the carts to cover the end of the clearo). It took a little forcing to get it to fit in the slot, but it'll go in, just dont put it down all the way, otherwise its super hard to get out. I was looking into modding the PCC but looks like there isn't much room to do so.