These handmade wool balls replace synthetic fabric softeners and dryer sheets. They keep heavy items such as sheets, blankets and jeans from getting balled up and allows your clothes to dry more evenly. Set of 4. Add a few drops of your preferred essential oil to the balls before starting the dryer to disperse the scent in your clothes. Reduce your drying time by a third because the balls promote efficient air flow which shortens drying time; prevents static cling too. Reusable up to 1000 loads and lasts 2-3 years! Hypoallergenic and 100% natural; perfect for sensitive skin!