Nikwax Cotton Proof adds water repellency to cotton and polycotton and maintains breathability, Prolongs the life of gear and optimises performance in wet weather, Easy to apply - can be used in a washing machine or by hand, no tumble drying required, Can be used on wet fabric, Inhibits rotting of canvas caused by dampness. Will not affect cosmetic appearance, WaterBased - environmentally friendly, biodegradable, non flammable, non hazardous, Does not contain fluorocarbons. Ideal for Cotton clothing and equipment such as tents, Polycotton clothing and equipment, and Canvas equipment. Nikwax..Easier, Safer, Drier.