Nikwax Down Proof has been specifically designed and optimized for down filled apparel and gear. It adds Durable Water Repellency (DWR), which protects against rain and condensation, improving the natural insulating properties of down. Nikwax Down Proof is a safe, easy to use product to wash and protect down filled gear. It is quick to apply in a washing machine and ensures that the DWR treatment goes right through the item, treating both the outer fabric, as well as the down fill. The DWR of Nikwax Down Proof develops when air drying, however, tumble drying at a low heat is recommended to ensure that the down is dried thoroughly and as quickly as possible. Leaving down wet or damp can ruin it indefinitely. The ideal product to keep your down items adventure ready for longer.