Over time, rain jackets can lose their water repellency. Water proofing does not last forever. Nikwax Waterproofers are a family of water-based water-repellent treatments you can apply to footwear, clothing, and gear. It is easy to clean and re-waterproof your rain jacket or your down jacket. Hiking shoes and boots are also easy to re-waterproof to keep your feet dry and comfortable.