Not sure what it was honestly, as I snapped the leads off. Anyhow I tried again tonight and got one working. Ohms are way too high this time at 3.0, but its working. Not sure how its different from the protank other than a slightly smoother draw and three times the weight, but I'll keep fussing with it.
Same as ProTank but too heavy.. hmmmm. I can fix that for you. I'll trade you my like-new Kanger ProTank 2 (box included) with 10 heads and a spare base for your kayfun. I could use another Kayfun, and my PT2 is sitting with the same juice in it that's been in there since I got my KFL lol.