The Ilford Rapid Fixer 5 Liter is a non-hardening rapid fixer that is ideal for developing films. It is supplied as a liquid concentrate that should be diluted with water before using. Instructions are provided with a 1+4 dilution for developing RC papers that should be fixed from 30 seconds to 1 minute, while the dilution will vary for the fiber based prints that should be fixed for 1-2 minutes. This fixer is ideal to be used in the temperature range of 18°C. Ammonium thiosulphate acts as the fixing agent in this fixer. It is suitable for fixing black and white film and paper in all manual and machine processing applications.