Adds Durable Water Repellency, revives breathability and maintains internal wicking properties. Breathable waterproof garments are most likely to get sweaty and wet inside when used in damp or wet conditions. If the outer fabric absorbs water, the garment can lose up to 70% of its breathability. Therefore, the Durable Water Repellency (DWR) on the outer fabric of your jacket must be maintained to ensure comfort. It will eventually wear off and need to be renewed with Nikwax TX.Direct.Nikwax TX.Direct Spray-On is a safe product to use on breathable waterproof items with wicking linings, or those that cant be machine washed. It is WaterBased, non-flammable, contains no volatile organic compounds (VOCs) and is fluorocarbon free. Nikwax TX.Direct Spray-On can be applied to the outer face fabric of waterproof clothing, providing Durable Water Repellency without compromising internal wicking properties.