Angel - Hopefully I can clear this up for you!
The JS comes stock with an 801 atty/cart.
Janty sells an 801 to 510 adaptor to allow you to use a 510 atty/cart on the Stick
The Janty unit sucks because it has a resistor in it that cuts down the voltage to the atty. Its also expensive at $20 + shipping. It's good though because it's long and places the 510 atty so it sticks out a bit to make it easy to put on/ take off.
AltSmoke sells an 801 to 510 adaptor that has no resistor and works great. The
vape from the 510 is same performance you'd get with a 510 batt, pass
thru or other 3.7 volt power source. The only issue with it is that it's reall short so it makes the 510 atty sit deep in the stick. You can either screw the adaptor down tight in the stick and then loosley attach the 510 atty or you can snug up the adaptor to the atty and loosely seat the whole thing in the stick.
From your post, I went to Healthcabin's site and they now sell an 801 to 510 adaptor for the stick that looks to have the best attributes of both mentione above. It looks to be all metal, the right length and hopefully has no resistor (no confr=irmation on this though). Best yet it's only $7 (but you always have to figure in Healthcabin's heft shipping rates!)
So hopefully this clears it up for you. BTW - I totally love my Janty Stick now that I'm using it with a 510 !!!!