Ilford Rapid Fixer supplied as a liquid concentrate that is diluted with water for use. It is easy and convenient to use in the temperature range of 18–40ºC (66–104ºF) for fixing black and white film and paper in all manual and machine processing applications. Ensure that all utensils, processing tanks or dishes/trays and mixing vessels are thoroughly rinsed and cleaned before mixing fresh batches, particularly if it is being used for the first time. Wash out the mixing vessels thoroughly after use. This product must not be used with fix hardeners. After filling a processor with fresh fixer tank solution, switch it on and allow it to get up to temperature and circulate the solutions. After the working temperature is reached leave it re-circulating for at least 10 minutes to ensure the fresh chemicals are thoroughly mixed before attempting to process any film or paper. Always replace the tank covers used on the process and replenishment solutions. The fixing agent in the Ilford Rapid Fixer is ammonium thiosulphate, it contains no sodium thiosulphate (hypo).