uhm rda's... well, when using one for a week, or two... the cotton changes color after every emtpy run, you could see when the cotton is worn, burn or damaged by eliquid coloring, the coils i do change them every 2 weeks on my main tanks, i use a rta the most, zeus single, this babe lasts 3 weeks intact, the problem are my dual coils, they last at much 2 weeks or week and some days,
REgards,
REgards,
