33 Colour Charts Parquet' are presenting for the first time certainty for installers, architects, designers and experts regarding colour changes of hard-, soft- and exotic woods before and after UV-exposure in fact in three ways: • Certainty in personal talks:Presenting future colour changes clearly and distinctly. • Certainty in planning:Optimizing selection of woods, preventing complaints. • Certainty if occurring colour changes:Comparing and judging certainly and definitely. The well-found methods of measuring, used in '33 Colour Charts Parquet', are providing certainty in all questions.