Stamps Mildew Stain Remover Lindner Germany ERNI A+B Treatment Not to be used on mint/gummed stamps. Instructions for use Before starting you should establish that it is mildew that you need to remove - this is different from foxing. To remove mildew stains from the stamps you need to prepare 3 trays. The first with Erni 'A' (purple liquid) the second with Erni 'B' (clear liquid) and the third tray with water. Soak the stamps you wish to clean in the first tray for about 3 minutes. Remove, allowing excess liquid to drip off the stamp (back into the tray). Now place stamps in second tray, containing the clear Erni 'B' liquid - soak for another 3 minutes then rinse in the final tray containing water - then dry. Please note the stamp will turn brown after soaking in Erni 'A' - the colour dissapears when soaked in Erni 'B'. Do not mix fluids 'A' and 'B' once used then can be disposed off safely by pouring down the drain.