There are several types of cotton forms when it comes to using the cotton for vaping. There are cotton balls, which at the peak of vaping was the only thing available to users that love to build atomizers and rebuildable tank atomizers. After the vaping industry grew and grew company’s started to come out with cotton pads that you would have to manually cut to a length necessary for you and us convenient for builders. After cotton pads, a popular hit was “cotton bacon” which are cotton strands from organic cotton, and soak up the juice and produce the best flavor. An all-time favorite for users in today’s vaping industry is Japanese Organic Cotton which is the most used and the most demanded type of cotton. Japanese organic cotton still has its natural color rather than cotton you buy at a local grocery store, it’s whitened with hydrogen peroxide. Cotton has become a need for vaping because it is a good carrier for vape juice and makes a difference depending on the atomizer you chose. You can replace cotton very easily on a rebuildable atomizer or on a rebuildable tank atomizer if you are tired of a juice or the cotton seems to be getting too dark or burnt. Cotton inside of a sub-ohm tank is not recommended to replace because the coil and the cotton come pre-installed into a coil head.