Winsor & Newton carefully formulates each tone for stability, tinting strength and coverage. Use them thickly with palette knives or brushes, or thin them to a very fine glaze.maximum pigment content consistent with good handling qualities, so optimum tinting strength can be achieved when the colours are reduced with white. 
The highest professional quality traditional oil colour made from the finest pigments,includes 37ml tube of Bismuth Yellow colour. 
Buttery, vibrant and consistent.