HARMAN WARMTONEDEVELOPER is a liquid concentrate suitable for the dish/tray developing of all RC and FB black and white photographic papers, but is particularly matched to Ilford Warmtone FB & RC papers, where it will bring out the warmest colouration of these papers. Used at a dilution of 1+9 it is clean working and has excellent keeping properties. We do not recommend its use for high temperature or machine processing applications. Not suitable for developing films. Although Harman Cooltone Developer is listed in the datasheet, this was discontinued a considerable time ago.