Heavy Filler is a very flexible filler used for fixing scuffs, scratches & holes in leather. The product is mainly used on areas of high use such as seating cushions & arms to fix damage where a long lasting & durable repair is required. For areas of cracking, use the Flexfil. Heavy Filler is a white paste, but with the addition of up to 10% Leather Colourant you can change the colour of the filler to match any colour.