What the Nikwax people say
Wash-in cleaner for waterproof clothing and equipment.
Safely revitalises breathability and water-repellency.
This product is a non-detergent soap which can be used regularly to clean clothing and equipment without damaging the Durable Water Repellent (DWR) coatings. Use this product instead of detergents or washing powder.
It does an amazing job, bringing jackets up to a near new look. My old Dainese textile jacket went from maroon sleeves back to red.
Note: I recommend hand washing bike gear and tents.