You can use any cartomizer on the k100. Brands are Boge, Smoktech, and Ikenvape. For a mechanical mod I'd recommend a low resistance (LR) cartomizer (2.0 ohm or thereabouts). Just be sure to fully fill the carto and to frequently top it off. If you allow the filler wick to get too dry you'll get a burnt taste which will never leave. And yes, it will be more comfortable to use a carto with a drip tip (mouth piece). You won't need to use a drip shield with a carto, those are for drip atomizers.
PROPER TERMINOLOGY: A GUIDE TO JUICE ATTACHMENTS
The best way to use a cartomizer is to use a "pre-punched" carto in a
cartotank. With each draw on the cartotank juice from the tank refills the carto and you won't have to worry about when to refill it because you can easily see the juice level in the tank. Cartos will need to be replaced every 2 - 3 weeks just like the replacement heads in a clearomizer.
BADITUDE'S CARTOTANK SETUP GUIDE
IBTANKED PYREX CARTOTANKS - A REVIEW
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