Nikwax Tech Wash 300ml. Nikwax Tech Wash 300ml is an easy to use wash in cleaner specially developed for waterproof textiles. Nikwax Tech Wash cleans effectively whilst reviving breathability and water repellency. Nikwax Tech Wash is recommended for Gore-Tex and eVENT items. Nikwax Tech Wash is applied in the washing machine which ensures the whole garment is cleaned. Nikwax Tech Wash is non-flammable, contains no harmful solvents and is free of harmful volatile organic compounds (VOCs) and fluorocarbons.