Ahhh - no wonder you are confused. We thought you meant the more common Vapor4Life's Vapor King which is a two piece model.
You have a 3 piece model of the same name (no idea which used that name first). I don't know what model Vapor King's "Vapor King" is, but you are correct, it has an atomizer (the middle part). It's probably a 510. 510's run a bit hot. But it shouldn't get excessively hot unless the atomizer (which we abbreviate atty) is not getting enough juice. Try topping off the cartridge more often with ejuice from a bottle.
Also if the juice-holding part of the cart is sort of a rectangle shape (i.e. 510 shape) try to line it up with the atty bridge
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The main thing is to make sure the cart has enough juice but not too much. And if the juice-holding part is that rectangular shape I mentioned, then when the white stuffing stops working well, try replacing it with blue foam cart stuffing. I don't really recommend this place's juices but the blue foam precut pieces for 510 are nice (easier than cutting your own)
https://strictlyejuice.com/index.php?main_page=product_info&products_id=222
For juice, I recommend FreedomSmokeUSA.com and use code freedomsmokeusa for 10% off
You can choose the PG/VG base of most of their their regular sizes of juice - I like 70pg/30vg or sometimes 80pg/20vg for more TH
I'm fond of their Desert Ship (a Turkish blend) and oRYental (a vanilla caramel tobacco) but they have lots of fruit and dessert flavors too and many other tobacco flavors. Note - not all flavors are available in the sample sizes and samples are all 24mg nic and fixed PG/VG