CL440 (medium grey) / CL440W (white) / CL440B (black) are part of the Challenger repair system. These robust, high solids universal fillers have very wide application windows and deliver excellent vertical stability as well as outstanding filling power and adhesion. The colours can be used on their own or can be mixed together to deliver the optimal undercoat colour for the subsequent topcoat colour. They provide great topcoat holdout of Challenger topcoats.