I use a EGO with XL atomizer. i recently bought some new xl atomizer however when i use then there is zero air flow, i cant suck. The only difference I can see with these new ones is the end that attaches to the battery (the insidebit with the hole in it) has a slight bigger diameter. I think the battery I have is 600mah. I know its not the carts i'm using as i tested with the cart it came with. i think this is the atomizer i purchased. Genuine eGo cylinder shape atomizer (Type B)