Excellent link, Kent.

Don did such a fabulous job on that guide!
I have a 901 to cartomizer adapter, and so I've been enjoying a cartomizer with various 3.7 volt, 5 volt, and 6 volt
devices. Wow. I've actually ordered a KR808 from PureSmoker to try out and see how well it works with the battery that is actually designed for the model.
But if what I've been experiencing is any indication, it's going to be a winner.
I vaped for HOURS on a single cartomizer. Finally noticed the vapor decreasing, so I unscrewed the cartomizer from the adapter and added about 15 drops (one at a time) of liquid into the small hole on the end of the cartomizer that screws into the adapter. I let it sit for a few hours, meanwhile
vaping on another cartomizer. When I went back to the original cartomizer, it lasted about 2 1/2 hours before vapor decreased again. (You can more fully refill the cartomizer, but I'm basically a lazy person.)
It will never totally replace my other setups, but it's easy and enjoyable . . . especially when I'm driving.
I am now
vaping with a cartomizer that has been refilled (in my lazy manner) 5 times. The atomizer is still going strong. Quite impressive.