Black Gesso Primer is a unique formulation which needs no dilution. This product is highly adhesive and is ideal for directly sealing all semi-absorbent surfaces before applying color – both acrylics and oils. Daler Rowney’s Black Gesso Primer is suitable for both interior and exterior applications. It dries quickly to produce a matt black surface, with a slight tooth, which is easily sanded for highly detailed work. If used as a ground for acrylics, one coat is normally sufficient, but up to three coats may be required for oil color.