I use Dura C Carts. I saw a video of GrimmGreen saying that they fit. Ordered a pack, then saw video where he said they leaked. Got my five carts in the mail and tried them. and all 5 work just fine for me. But like previous post says, there is still juice in the cart. Unless you've pulled the filler out and looked at it, i wouldn't say you are smoking them dry.