Made of 100% fragrance free, unbleached New Zealand sheep wool, Super Bee Wool Dryer Balls not only help soften your clothes in the tumble dryer they also help to reduce drying time by up to 30%. Lasting for up to 1, 000 loads, at the end of their life, they are biodegradable & compostable. If you prefer a fragrance to your clean clothes, add a few drops of your favourite essential oil directly to the wool balls a couple of hours before using. Your clothes will be infused with a subtle, chemical-free fragrance.