Handmade High Quality wool. The organic woollen balls are Hypoallergenic, no allergies, no toxins, 100% premium wool. The blended fibres are completely organic. Reusable. These woollen balls can be used hundreds of times in the tumble dryer to speed up the drying process, remove lint and reduce static from the laundry load! Set of 4. The four balls are 7cm in diameter which is the optimum size for efficient drying and enough to put into any sized drying machine. Energy saving. The drying time can be reduced by up to 40%, lowering your energy bills and being more eco-friendly!