Cotton wool is a loose, loose form of moksa.
Moksa is used to stimulate acupuncture points through the high temperature generated by burning moxa. During combustion, it gives off intense smoke and soothing scent. It can be used alone or in bamboo containers or with the use of caps.
The color of the moxa shows its purity. The more yellow the moxa, the purer it is. It does not contain stems or leaves, only the fluff of plants.