I think what they're referring to is just the threads for the eGo cone, since the actual atomizer connector on the eGo is just a 510. I can understand why they are asking this. With some eGo gear (particularly with the Giantomizers and eGo dual-coils) the draw can be too light on certain setups. For those I actually use an adapter that has the eGo cone threads and this optimizes the air flow for those cartomizers. I've also heard of at least one cartomizer that actually uses those larger threads to attach, but this is not common and I have not personally had any experience with them