Nikwax says about the TX Direct Wash-In
For waterproofing rain gear. Easy to use wash-in waterproofing for all breathable waterproof clothing and gear. Adds water repellency and revives breathability without tumble drying. Enhances the performance of your gear, keeping you warmer and drier. Recommended for Gore-Tex®, Sympatex®, eVent®, Nikwax Analogy® and all other waterproof fabrics.