Buy natural essential oil to use in your laundry with wool dryer balls. A natural oil typically having the characteristic odour of the plant, essential oils are 100% pure aromatic distillates. Natural Essential Oils are used to bring fresh scents into your clothing to your laundry. How to use essential oil? well after the laundry is dried, add few drops of oil to the dryer balls, put them back in the dryer and run on very normal heated scale for 7 to 10 minutes. That's it, check your smart clothing with best perfume works.